George Ball, undersecretary of state in the Democratic administration, also warned in what today would be considered insensitive language that using a nuclear response could subject the country to charges of racism following the twin atomic bombings in Japan that ended World War II.
"If there is a general appearance of a shift in strategy to the dependence on a nuclear defence against the Chinese in the far east, we are going to inject into this whole world opinion the old bugaboo of being willing to use nuclear weapons against Asians when we are talking about a different kind of strategy in Europe," Ball told the president during a May 9, 1963, national security meeting in the White House.
"This is going to create great problems with the Japanese -- with all the yellow people."
A six-page summary of the top-secret meeting was released in 1996, but a tape of the conversation was made available only after it was subjected to a national security review based on updated federal guidelines.
In one exchange on the tape, Army General Maxwell Taylor, then chairman of the joint chiefs of staff, is heard telling Kennedy, "Mr president, I had hoped before we get too deeply in the India question, we take a broader look at where we are coming, the attitude we're going to maintain versus red China. This is just one spectacular aspect of the overall problem of how to cope with Red China politically and militarily in the next decade. I would hate to think that we would fight this on the ground in a non-nuclear way."
Later, when Kennedy begins discussing the idea of guaranteeing India's security, then defence secretary Robert McNamara steers the conversation back to China.
"Mr president I think General Taylor is implying that before any substantial commitment to defend India against China is given, we should recognise that in order to carry out that commitment against any substantial Chinese attack, we would have to use nuclear weapons. Any large Chinese Communist attack on any part of that area would require the use of nuclear weapons by the US, and this is to be preferred over the introduction of large numbers of US soldiers."
The recording, released by John F Kennedy Presidential Library -- the official repository of Kennedy administration documents -- runs 165 minutes, of which 33 are devoted to the national security meeting. The tape also includes meetings about civil rights issues and North Atlantic Treaty Organisation issues.
The then-Secretary of State Dean Rusk had said "I think we would be hard pressed to tell our own people why we are doing this with India when even the British won't do it or the Australians won't do it and the Canadians won't do it. We need to have those other flags flying on these joint enterprises."
Kennedy was assassinated in November 1963, before he could issue such a guarantee. The minutes paraphrase him saying, "It was obvious we would defend India if attacked," so the US "should go some of the way now towards gaining the benefits prior to an attack of a defence commitment."
"If we were overrun in Korea, in Formosa or in Western Europe, we would obviously use nuclear weapons." If the United States was braced for that commitment, he asked why "we should not be prepared to commit ourselves to defend India."