http://www.telegraph.co.uk/history/9628028/The-assassination-of-President-John-F-Kennedy-the-finger-points-to-the-KGB.html

Nearly 50 years on, a new book suggests that assassin Lee Harvey Oswald was guided by hardline Stalinist dissidents

The young American was agitated, increasingly emotional, and had laid a loaded gun on the table. The Soviet Union must grant him a visa as soon as possible, he pleaded. His life was being made intolerable by FBI surveillance and he, a dedicated communist, wished to return to the arms of Mother Russia.

One of the three Soviet diplomats present took the gun and unloaded it before returning it to its owner. There would be no visa in the near future, he explained calmly. Dejected, the American gathered up his documents and departed the Soviet consulate, bound not for his previous home in New Orleans, but Dallas. It was Mexico City, Saturday, September 28 1963, and the man wanting the visa was Lee Harvey Oswald. Fifty-five days later, he would assassinate John Fitzgerald Kennedy, 35th president of the United States.

This is the standard version of events, as related by one of the “diplomats” present that day, Oleg Nechiporenko. The other two were Pavel Yatskov and Valery Kostikov. All were, in reality, officers in the KGB. Kostikov was, according to the CIA, attached to Department 13 of the First Chief Directorate, specialising in “executive action” – sabotage and assassination.
Half a century later, two great traumas of the Cold War era stir in the memory – the Cuban Missile Crisis of October 14-28 1962 and the Kennedy assassination on November 22 the following year. The 50th anniversary of the latter is bound to reignite debate about that fateful lunchtime in Dealey Plaza. In his book, Reclaiming History, the lawyer Vincent Bugliosi expends 1.5 million words proving that Oswald was the lone gunman.

Many disagree, not least the US House of Representatives Select Committee on Assassinations, which in 1979 concluded that, in all probability, two gunmen were involved – and Kennedy was, therefore, the victim of a conspiracy. In its findings, the committee concluded something else, that the Soviet government had not been involved in the assassination. In 1979, the nuclear stand-off between East and West had a decade to run, and the finding was as necessary then as in 1963, when a declaration of Soviet involvement could have triggered a thermonuclear war.