The debate is off. The one scheduled for May 27 in the Oxford Union between Defense Secretary Caspar Weinberger and Prof. E.P. Thompson, a leading supporter of nuclear disarmament.
Nobody seems too precise about the issue to have been contested. The occasion was advertised simply as ''a nuclear debate.''
Nobody seems certain why it was canceled. American officials said work was piling up at the Pentagon and, besides, Mr. Weinberger didn't want to 'interfere'' in a British general election - in case one was called.
The Guardian ran a story that British Defense Minister Michael Heseltine had warned Mr. Weinberger of Professor Thompson's prowess as a debater. The nasty hint was that our Daniel Webster had been frightened away.
It is difficult to believe the Guardian's explanation. A man like Mr. Weinberger, who has faced the possibility of nuclear warfare with more equanimity than a lot of us can muster, would scarcely cower before the secret weapons of an English debater.
Mind you, there are few things more intimidating than an Englishman in full battle cry, either as a debater or as a writer of absolutely terrifying letters to the editor.
We have a mismatch of styles here.
The American, when he wishes to argue, tends to set himself up as a dispassionate exerciser of pure logic.
The English antagonist gets straight to the point by going personal (''My worthy friend here alleges . . .'') - and the more personal the better.
When dealing with a colonial, an Oxford Union heckler can be counted upon to wait until the poor alien takes the first liberty with the mother tongue. For example, if the secretary - falling into a currently popular adverbial confusion - had said, ''Hopefully, there will be no war, nuclear or otherwise,'' the trap would have sprung: ''Hopefully? Hopefully? (pause) You might at least do us the small courtesy of learning our language.''
This classic case of patrician scorn is to be found - from pause on - in ''Middle Class Education,'' an Oxford novel by Wilfrid Sheed, whose personal experience as a child of two cultures makes him an authority on Anglo-American encounters.
Other remarks by Mr. Sheed shrewdly measure the risk of transatlantic strangers, like Mr. Weinberger, who must grasp the peculiar combination of paradox and sneer that prevail in upper-class English debate. One of Sheed's Oxford chaps observes: ''In America I believe they specialize. The funny people make the jokes, and the others keep strong and quiet.''
Of Americans who have recently entered the den of the Oxford Union, perhaps only John Kenneth Galbraith mastered the paradox and only William F. Buckley the sneer.
If - we say if - Mr. Weinberger is just a bit daunted by those sharp blades that can, as it were, slice tomatoes without spilling the juice, he should not apologize. The English are intimidated by the Oxford Union too. The difference is, they handle it in an Oxford Union way - with amused superiority.
Here is Lady Antonia Fraser, condescending to her visit at the Union: ''I certainly wasted an evening. I cannot remember one word of the debate.''
Here is Nigel Nicolson, looking back in languor: ''Once I spoke in a Union debate, late at night . . . I did not possess the charismatic gift.'' Even on the printed page you can almost hear the sniff.
Jo Grimond, leader of the Liberal Party for a decade, put the Oxford Union in its place as stylishly as anybody. ''I was interested in politics,'' he recalls of his Oxford days, ''but I was never a member of the Union. Over this I have no regrets.'' He goes on to suggest that the Union ''has been a little responsible for the superficiality of much political comment, the sneering, the desire to be on the inside.'' With devastating understatement he concludes: ''To have attended the debates I would have had to give up something else.''
If Mr. Weinberger could sneer against the sneerers like this, he might have converted even his cancellation into a moment of triumph. On the other hand, anybody who can curl a lip that expertly might as well show up and win.