It was March 1963, the height of the Cold War - a time of covert U.S. government assassination plots against Fidel Castro, Kennedy administration-sponsored exile raids and sabotage missions directed at Cuba.

It was also a time when Castro - still smarting from Moscow's failure to consult him about the withdrawal of missiles from the island in 1962 - was sending feelers to Washington about Cuba's interest in rapprochement.

President John F. Kennedy responded by overruling the State Department's position that Cuba break its ties with Soviet bloc nations as a precondition for talks on normal relations, according to an account to be published this week in the October issue of Cigar Aficionado magazine.

"The President himself is very interested in this one,'' says a March 1963 top-secret White House memo. ``The President does not agree that we should make the breaking of Sino-Soviet ties a non-negotiable point. We don't want to present Castro with a condition that he obviously cannot fulfill. We should start thinking along more flexible lines.''

The article, JFK and Castro: The Secret Quest for Accommodation, is based on recently declassified documents and written by Peter Kornbluh, a senior analyst at the Washington-based National Security Archive, a nongovernmental research institute. It traces the secret U.S.-Cuban contacts during the last months of the Kennedy administration and into the Johnson administration.

Although the general outlines of the contacts have been known, the account adds considerable detail, particularly the key role played by the late ABC correspondent Lisa Howard, who interviewed Castro in April 1963.

In addition to Howard, key players were McGeorge Bundy, the Kennedy and Johnson administrations' national security advisor, his assistant Gordon Chase and William Attwood, former Look magazine editor who at the time was an advisor to the U.S. mission at the United Nations.

On the Cuban side, the principal players were Carlos Lechuga, Cuba's U.N. ambassador, and Rene Vallejo, Castro's personal physician.

Initial overtures from Castro to Washington in late 1962 had been made through New York lawyer James Donovan, who had been enlisted by the Kennedy administration to negotiate the release of Bay of Pigs prisoners.

Efforts at normalization languished, however, until the involvement of Howard and Attwood started to bear fruit in the latter part of 1963.

In September, Attwood was authorized to have direct contacts with Lechuga, which were arranged by Howard at a Sept. 23 reception in her New York apartment. Attwood was to subsequently confer with Vallejo by telephone from Howard's apartment or she would relay messages between the two.

At one point, Vallejo conveyed a message to Attwood through Howard that said, "Castro would like to talk to the U.S. official anytime and appreciates the importance of discretion to all concerned. Castro would therefore be willing to send a plane to Mexico to pick up the official and fly him to a private airport near Varadero where Castro would talk to him alone. The plane would fly him back immediately.''

The invitation touched off a debate within the White House, with President Kennedy's position being that "it did not seem practicable'' to send an American official to Cuba "at this stage.''

Even so, the contacts continued to gain momentum until Kennedy's assassination on Nov. 22, 1963, when the "Attwood-Lechuga tie line'' was put on hold, with White House aides concerned that assassin Lee Harvey Oswald's reported pro-Castro sympathies would make an accommodation more difficult.

The back-channel contacts continued under President Lyndon Johnson through 1964, according to Kornbluh, but fizzled out in late 1964 as the fall presidential elections approached, despite ongoing efforts by Howard to keep them alive.

In December 1964, Howard made her final and unsuccessful effort by trying to arrange a meeting in New York between U.S. officials and Ernesto "Che'' Guevara, the Argentine-born Cuban revolutionary.

A few days before his assassination, President Kennedy was planning a meeting with Cuban officials to negotiate the normalisation of relations with Fidel Castro, according to a newly declassified tape and White House documents.

The rapprochement was cut off in Dallas 40 years ago this week by Lee Harvey Oswald, who appears to have believed he was assassinating the president in the interests of the Cuban revolution.

But the new evidence suggests that Castro saw Kennedy's killing as a setback. He tried to restart a dialogue with the next administration, but Lyndon Johnson was at first too concerned about appearing soft on communism and later too distracted by Vietnam to respond.

A later attempt to restore normal relations by President Carter was defeated by a rightwing backlash, and since then any move towards lifting the Cuban trade embargo has been opposed by Cuban exile groups, who wield disproportionate political power from Florida.

Peter Kornbluh, a researcher at Washington's National Security Archives who has reviewed the new evidence, said: "It shows that the whole history of US-Cuban relations might have been quite different if Kennedy had not been assassinated."

Castro and Kennedy's tentative flirtation came at a time of extraordinary acrimony in the wake of US-backed Bay of Pigs invasion by Cuban exiles and the missile crisis which led the world to the brink of nuclear war.

It began with a secret and highly unorthodox dialogue conducted through an intrepid journalist and former soap-opera actor and involved plans to fly a US diplomat from Mexico to Cuba for a clandestine face-to-face meeting with Castro alone in an aircraft hangar.

On a newly declassified Oval Office audiotape, recorded only 17 days before the assassination, Kennedy can be heard discussing the option with his national security adviser, McGeorge Bundy.

The president agrees in principle to send an American diplomat, Bill Attwood, who had once interviewed Castro during a former career as a journalist, but he fretted that news of the secret mission would leak out. At one point Kennedy asks: "Can't we get Mr Attwood off the payroll?" If the diplomat was no longer on staff the whole trip would be deniable if it came to light.

Kennedy had been thinking about reopening relations with Havana since spring that year.

The key intermediary was Lisa Howard, an actor who had become a leading television journalist when she managed to land an interview with the Soviet leader, Nikita Krushchev.

In April 1963, she scored another coup - an interview with Castro, and returned with a message for the Kennedy administration, that the Cuban leader was anxious to talk. The message launched a frantic period of diplomacy, recounted in a television documentary broadcast last night on the Discovery Times channel, entitled "A President, A Revolutionary, A Reporter".

The president was receptive. The CIA was pursuing various schemes aimed at assassinating or undermining Castro, but Kennedy's aides were increasingly convinced Havana could be weaned away from Moscow.

In one memorandum a senior White House aide, Gordon Chase, says: "We have not yet looked seriously at the other side of the coin - quietly enticing Castro over to us," instead of looking at ways to hurt him.

According to Mr Bundy, Kennedy "was more in favour of pushing towards an opening toward Cuba than was the state department, the idea being... getting them out of the Soviet fold and perhaps wiping out the Bay of Pigs and getting back to normal".

The administration gave a nod to Ms Howard, who set up a chance meeting between Mr Attwood and the Cuban ambassador to the UN, Carlos Lechuga, at a cocktail party in her Park Avenue apartment.

The apartment then became a communications centre between Mr Attwood and the Castro regime. Castro's aide, Dr Rene Vallejo, called at pre-arranged times to talk to Mr Attwood, and in the autumn of 1963 suggested that Mr Attwood fly to Mexico from where he would be picked up by a plane sent by Castro. The plane would take him to a private airport near Veradero, Cuba, where the Cuban leader would talk to him alone in a hangar. He would be flown back after the talks.

Kennedy and Bundy discuss the plan on the tape on November 5. The national security adviser does much of the talking but the president is clearly worried that the trip will be leaked. First he suggests taking Mr Attwood off the state department payroll, but later he decided even that was too risky. Instead, he suggested Dr Vallejo fly to the UN for a confidential meeting to discuss the agenda of direct talks with Castro.

The plan, however, was sunk by the assassination. Ms Howard continued to bring messages back to Washington from Castro, in which the Cuban leader expresses his support for President Johnson's 1964 election and even offers to turn the other cheek if the new US leader wanted to indulge in some electoral Cuba-bashing. But the Johnson White House was far more cautious. The new president did not have the cold war credentials of having faced down the Soviet Union over the Cuban missile crisis. The moment had passed.

Secretary Senator McCarthy outlined the main points of his December 16 conversation with Che Guevara, Cuban Minister of Industry. The meeting was arranged directly with the Senator by Lisa Howard and took place in her New York apartment.

The Senator said he believed the purpose of the meeting was to express Cuban interest in trade with the US and US recognition of the Cuban Regime. Mr. Ball agreed this was plausible, saying that because of the state of the Cuban economy, the Cuban Regime was interested in reviving its trade relations with the US to obtain convertible currency. Further, he felt that Guevara probably recognized that any dealings with the US would add respectability to the regime in the eyes of other Latin American States.

Guevara told Senator McCarthy the Alliance for Progress would fail because it merely underwrites vested interests and the status quo. He said that Venezuela and the Central American States in particular needed revolutions. Chile was one state that was undertaking reforms that might make a revolution unnecessary. He noted that Chile would recognize Cuba if it were not for United States pressure.

Guevara did not attempt to conceal the subversive activities which Cuba was undertaking. He explicitly admitted that they were training revolutionaries and would continue to do so. He felt that this was a necessary mission for the Cuban Government since revolution offered the only hope of progress for Latin America.

Guevara attacked United States' overflights but not in particularly belligerent terms. He said that Cuba had the means to shoot down the planes, but had not taken any action against the United States. He insisted that there was no juridical basis for the overflights and that such a juridical basis was not furnished by OAS approval. Guevara mentioned only one specific "violation of sovereignty", this being when a US helicopter landed "over the line" (presumably at Guantanamo). He said that in this case, after some talk of firing upon the helicopter, it was permitted to leave Cuban territory.

Guevara said he knew the CIA was in Cuba. He stated that most of Cuba's enemies worked for the oil and power companies. He said the regime could identify them and they in turn knew they would be shot if they resorted to sabotage.

Guevara took issue with a statement that Ambassador Stevenson had made that the US was not withholding shipments of drugs to Cuba. Mr. Mann commented that drug shipments may have been cut back and that this was one area in which the Cubans could score on us. Mr. Ball said there was no reason why we should not sell drugs or medicines to Cuba, and Mr. Mann said he would look into the matter.

Guevara told the Senator that while conditions in Cuba were not good, there was no question of the regime collapsing. On the question of refugees, he said Cubans who did not like life on the island were free to leave. Mr. Mann commented that this was not true. Guevara also said the regime did not want any refugees returned to Cuba.

On relations between the Government and the Catholic Church, Guevara said they were good but that Party members could not belong to the Church. He mentioned in passing that they had more problems with Protestants than with Catholics.

On free elections, Guevara said these had not taken place because the revolution had not fully evolved. As to what form of government might eventually develop in Cuba, Guevara said—with pointed reference to Senator McCarthy—there was no interest in a bicameral congress or in anything along the lines of the Supreme Soviet in the USSR. He commented that the latter had no real power.

Mr. Ball asked if any references were made to Cuba's relationship to Moscow. It was mentioned that Lisa Howard had made the point that better relations with the US would give Cuba a more desirable position vis-א-vis Moscow. Mr. Ball said he believed the USSR was becoming fed up with Cuba but felt compelled to continue supporting it because of its symbolic importance as the first country to go communist without pressure of the Red Army.

Mr. Ball emphasized the danger of meetings such as that which the Senator had had with Guevara. There was suspicion throughout Latin America that the US might make a deal with Cuba behind the backs of the other American States. This could provide a propaganda line useful to the Communists.

Mr. Ball pointed out that Guevara could not move about without a great many people knowing where he was and whom he was seeing. McCarthy agreed, mentioning the large number of police cars that had gathered when he met Guevara. Mr. Ball asked that McCarthy get in touch with him if any further contacts with Guevara were contemplated. Meanwhile it was essential that nothing be publicly said about the McCarthy–Guevara meeting although there was danger that Guevara himself might leak it.

Eugene McCarthy, the senator for Minnesota (1959-71) who has died at the age of 89, occupies a strange niche in American history. In 1968, with the backing of just 28,791 electors from one of the country's smallest states, he effectively unseated President Lyndon Johnson, who had been returned to the White House by a 60% landslide only three years earlier. Between these two events, of course, Johnson had been prosecuting the disastrous war in Vietnam. The most dramatic indicator of its eventual outcome - America's first military defeat - had come on January 30 1968 with North Vietnam's Tet offensive against 36 Southern towns. This attack not only caught US forces by surprise but brought to America's domestic hearths almost unbelievable television pictures of US marines fighting within the grounds of their own embassy in Saigon to prevent its being overrun by the Vietcong.

Just six weeks later came the first stage of that year's presidential election, the New Hampshire primary. It had been preceded by frenzied activity from a small group of anti-war campaigners who called themselves the Alternative Candidate Task Force. Rather than embark on a forlorn third party campaign to stop the war, they had decided to find a senior Democrat prepared to oppose Johnson's re-nomination as the party's candidate. In October 1967, having been turned down by some 20 senators and representatives, they finally persuaded the maverick Senator McCarthy to take his political life in his hands.

McCarthy had never been in the Democratic mainstream, though he had come to national attention with a speech at the party's 1960 convention urging Adlai Stevenson's nomination (the delegates preferred John Kennedy). He had also shown notable hostility to his fellow Minnesotan, Johnson's vice-president Hubert Humphrey. How much that feud figured in his decision to run was never clear.

McCarthy had not previously opposed the war and had voted in 1964 for the Tonkin Gulf resolution that gave Johnson almost unfettered authority to escalate the conflict. Later, on the New Hampshire stump, McCarthy was to comment that: "Escalation is a word that has no point of interruption. By the time you raise the question the flag has gone by."

Indeed, as the war ground on, the mood in the country had shifted dramatically, particularly among those most closely affected: university students liable for conscription. McCarthy's daughter, then in her first year at college, had frequently discussed this burgeoning dissent with her father. As the postwar baby bulge moved through the education system it had provided America with some seven million students by 1968. As a political lobby they outnumbered almost every other single group and comprised, therefore, a powerful force for any candidate to mobilise. When McCarthy formally announced his candidacy on November 30 1967, students began to flock to his colours.

The shock of the Tet offensive, combined with the proximity of Harvard and Yale universities to New Hampshire, brought McCarthy a seemingly endless flood of young campaigners. McCarthy offered almost the ideal hero figure...

At the beginning of January 1968, the Gallup poll registered 12% support for McCarthy; by the beginning of March that had grown to 28%. When the returns for the Democratic primary were completed on March 12, McCarthy had secured 42.4% of the vote to Johnson's 49.5%. But, when Republican write-in votes were added, the president had managed to poll only 230 more than McCarthy in a contest that should have been a White House walkover.

It had an immediate and profound effect. No one had imagined for a moment that an incumbent president might suffer such a humiliation. Four days later, Senator Robert Kennedy announced his own entry into the contest, a move that produced a memorable response from one of McCarthy's student helpers. "After the primary," she said, "it was like Christmas Day. Then, when we went down to the tree, we found Bobby had stolen all our presents." While McCarthy won primary victories in Wisconsin, Pennsylvania, Connecticut and Oregon, Kennedy won Indiana and then, in June, California. Only hours after his victory, Kennedy was assassinated.

Meanwhile, on March 31, Johnson had announced his withdrawal from the election, and Martin Luther King had, too, been assassinated. The Democratic campaign culminated at its convention in Chicago. There, on August 28, Vice-President Humphrey, who had not entered a single primary, was nominated as the Democratic candidate while the Chicago police, on the orders of Democrat mayor Richard Daley, indiscriminately tear-gassed anti-war demonstrators, delegates and passers-by. "I can still smell the tear gas in the HIlton Hotel," McCarthy said nearly 20 years later.

I was a child when Sen. Eugene McCarthy led the "children's crusade."

This does not insulate me from the long, hot blowback against McCarthy's 1968 presidential bid, which forced Lyndon Johnson from office and forced the American public to examine the Vietnam War in a way that it had not examined it before.

From time to time, a reader who disagrees with something I've written on a subject that has nothing whatever to do with Vietnam tells me that I "hate America." I am accused of having been one of the unkempt liberal kids who took to the streets during the tumult of those times, and so ruined the country.

Truth is, I was 12 when McCarthy stunned the political establishment by breaking with his party to oppose the war policy of an incumbent president. My hometown did not send its children safely off to college with deferments but saw its sons get their high school diplomas - followed quickly by their draft notices.

When I was 12 I was not out to transform the world but was engrossed in a transition that involved the abandonment of Barbie dolls in favor of Beatles records.

And so I read the obituaries of McCarthy, who died over the weekend at 89, not with the misty eye of nostalgia but with a deep curiosity about what it was that drove the man to do what he did - take on the Democratic Party, take on its incumbent president, take up the anti-war cause that had been mostly confined to college campuses, the "children's crusade."

For better and for worse, McCarthy's legacy has a sharp and painful edge.

His act of courage changed history, but not nearly fast enough. He would not become president; Richard Nixon would. The Vietnam War continued for another five years, expanding into Cambodia, spawning more domestic turmoil and the killing of students at Kent State and Jackson State universities. About 30,000 Americans had been killed in Vietnam as of January 1969, when Nixon took office. Another 28,000 would die before the American military involvement ended.

Is there anyone now who would call those years between 1968 and 1973 necessary - let alone, victorious? With tens of thousands dead and the country's reputation in tatters, why is it that the political backlash against those who opposed the Vietnam War has endured? It is a fault line deep and damaging, and defines our politics to this day.

The sense of grievance that began coursing through the body politic four decades ago still quickens conservative blood, and politicians on the right exploit it with expertise.

When Rep. John Murtha (D-Pa.), a decorated Vietnam veteran and longtime defense hawk, called recently for a quick withdrawal from Iraq, the White House denounced him as adopting the policies of "Michael Moore and the extreme liberal wing of the Democratic Party."

When Democratic National Committee chairman Howard Dean, in a radio interview, said "the idea that we're going to win the war in Iraq is an idea which is just plain wrong," Republicans attacked - and fellow Democrats ran for political cover. In fact, Dean hadn't advocated withdrawal but a drawdown of U.S. troops over two years, with some re-deployed to Afghanistan.

Besides, what would victory in Iraq look like?

In April 2003, we were led to believe triumph could be seen in the toppling of Saddam Hussein's statue. A month later, the president landed on an aircraft carrier festooned with a banner proclaiming "Mission Accomplished." Last February, congressional Republicans dipped their fingers in purple ink and held them aloft during President Bush's State of the Union speech, effectively proclaiming the U.S. had won because Iraqis had held their first election.

You do not have to have backed McCarthy in 1968 to see the parallels to Vietnam, with its shifting military goals and the empty promise of "peace with honor." But there will not now be another McCarthy.

Few Republicans question Bush's conduct of the Iraq War, and they quibble mostly over details. Democrats are split. They fear the inevitable label of being called "soft on Iraq."

In truth, the bitter legacy of Eugene McCarthy - a man who stood on principle for a cause larger than himself - is that he has been succeeded in politics by men who lack principle, and have as their cause themselves.

Former Sen. Eugene J. McCarthy, who died last week at 89, was the most paradoxical of the major political figures of his time.

A deeply serious and religious man, an educator and a poet, he also had a wicked sense of humor and a great gift for satire. One day in the late 1950s, when liberal maverick Sens. Wayne Morse of Oregon and Ernest Gruening of Alaska, who were always in the doghouse of Senate Majority Leader Lyndon Johnson, fell into a dispute with each other, Mr. McCarthy strolled by the press table in the Senate restaurant.

"Trouble in the leper colony," he observed, deadpan.

Mr. McCarthy defied easy categorization. A product of rural Minnesota, educated by the Benedictines and married to a woman, the former Abigail Quigley, every bit as capable a writer and thinker as himself, he was taken up in his 30s by the Minnesota Democratic-Farmer-Labor Party, which was led then and for decades afterward by Hubert H. Humphrey.

He ousted a Republican incumbent to win the House seat from St. Paul, became an early ringleader of the reform-minded Democratic Study Group and moved on to the Senate in the big Democratic sweep of 1958. A renowned orator, he wrote and delivered a nominating speech for Adlai Stevenson at the 1960 Democratic National Convention that set off a wild demonstration in the galleries in Los Angeles – and gained him the enduring enmity of the Kennedy clan, which was about to nominate one of its own for president.

However, Mr. McCarthy was hardly a national figure when Allard Lowenstein and other leaders of the "dump Johnson" movement approached him in 1967, seeking an anti-Vietnam candidate who would challenge the president in the 1968 primaries. Mr. McCarthy had broken publicly with President Johnson on the war and was still nursing wounds from being passed over in 1964, when the Texan chose Mr. Humphrey as his running mate.

But Mr. McCarthy was characteristically reticent and ambivalent at the outset of the campaign, insisting in almost academic fashion that he was not "running" for president but was "willing" to serve.

For all his reluctance, he was a magnetic figure for young people and for the broad swath of Democrats who had come to oppose the war. If Vietnam fueled his dissent, he insisted that his purpose was larger – and less personal – than for most candidates. In his fine double-biography of Mr. McCarthy and Mr. Humphrey, Almost to the Presidency, journalist and fellow Minnesotan Albert Eisele quotes this passage from Mr. McCarthy's November 1967 declaration of candidacy:

"I am hoping that this challenge I am making, which I am hoping will be supported by other members of the Senate and by other politicians, may alleviate the sense of political helplessness and restore to many people a belief in the processes of American politics and of American government." No more selfless manifesto was imaginable.

The response was extraordinary. College students by the thousands scrubbed up "clean for Gene" and hit the campaign trail in New Hampshire and later primaries. Even after all the stunning events that followed – Robert Kennedy's entry into the race, Mr. Kennedy's murder, the bloody Chicago convention that nominated but crippled Mr. Humphrey and the election of Richard Nixon – scores of those McCarthy volunteers remained in politics, fueling a generation of Democratic activism.

Oddly, Mr. McCarthy was uncomfortable with the personal adulation. As ambitious as Mr. Humphrey, he was far more remote and self-centered - the opposite of a glad-handing politician. I saw him as someone who deliberately distanced himself from his closest political allies - even when he pursued his ambition to become Mr. Johnson's running mate, while almost all his old comrades labored to get Mr. Humphrey onto the ticket.

His last years were not happy ones. I heard him in a forum a few years ago, and his talk was a recital of grievances - directed at people either dead or long retired, who had failed in Mr. McCarthy's still-harsh judgment to meet their responsibilities in that 1968 crucible.

Although he supported the Korean War, McCarthy said he opposed the Vietnam War because "as it went on, you could tell the people running it didn't know what was going on."

"I admired Gene enormously for his courage in challenging a war America never should have fought," Sen. Edward M. Kennedy, D-Mass., said Saturday. Drawing a parallel to the current debate within the Democratic Party over the Iraq war, Kennedy said, "His life speaks volumes to us today, as we face a similar critical time for our country."

Former Sen. George McGovern, D-S.D., said McCarthy's presidential run in 1968 dramatically changed the antiwar movement. "It was no longer a movement of concerned citizens, but became a national political movement," McGovern said Saturday. "He was an inspiration to me in all of my life in politics." McGovern won the 1972 Democratic presidential nomination, when McCarthy ran a second time.

Former Sen. John Edwards, D-N.C., who ran for vice president in 2004, said McCarthy "was a remarkable American, a man who spoke his conscience, and he was a great leader for my party."

In recent years, McCarthy was critical of campaign finance reform, winning him an unlikely award from the Conservative Political Action Conference in 2000. In an interview when he got the award, McCarthy said money helped him in the 1968 race. "We had a few big contributors," he said. "And that's true of any liberal movement. In the American Revolution, they didn't get matching funds from George III."

After the attacks of Sept. 11, 2001, McCarthy said the United States was partly to blame for ignoring the plight of Palestinians. "You let a thing like that fester for 45 years, you have to expect something like this to happen," he said in an interview at the time. "No one at the White House has shown any concern for the Palestinians."

In a 2004 biography, "Eugene McCarthy: The Rise and Fall of Postwar American Liberalism," British historian Dominic Sandbrook painted an unflattering portrait of McCarthy, calling him lazy and jealous, among other things. McCarthy, Sandbrook wrote, "willfully courted the reputation of frivolous maverick."

In McCarthy's 1998 book, "No-Fault Politics," editor Keith C. Burris described McCarthy in the introduction as "a Catholic committed to social justice but a skeptic about reform, about do-gooders, about the power of the state and the competence of government, and about the liberal reliance upon material cures for social problems."