A disturbingly straightforward ghoul that has merely giggled at the discussion of foreign policy in the last four television debates grew solemn this week. The suspicion that the candidates' impulsive exchanges of facile polemic on complex problems of foreign policy were, at the least, ill-considered, expanded into violent criticism of their stands.

The U.S. allies in NATO conceived this worrisome ghoul. They are understandably distressed at Nixon's suggestion that Quemoy and Matsu should be defended under any and all circumstances and at Kennedy's call for assistance to overthrow Premier Castro's government. Their idea has been that such matters are at the discretion of the President and of the State Department. Mere candidates in their view should ignore their conventions' proclamations that foreign policy is the most important issue in the campaign. Our allies would prefer, according to Mr. Reston in yesterday's New York Times, that Kennedy and Nixon refrain from saying anything more about any aspect of U.S. foreign relations.

But Kennedy sounds good on television, and wants a fifth debate. Nixon has found his opponents over-whelmingly weak spot in the issue of Cuba, and will accept another debate if he can be sure Cuba will be the topic. Stir into this frenetic brew of telegrams Kennedy's assertion that the vice-President is "afraid" to debate with him and Nixon's statement that such an assertion is "sophomoric" and the lurch toward a fifth debate grows overpowering in its momentum.

Yet if another debate is really to talk about Cuba, aand perhaps about Quemoy and Matsu as well, it is likely to give not only NATO but also the State Department a good deal of unnecessary anguish. Neither body wants to see men not in a position to make policy decision doing exactly that, and both resent seeing their best-laid plans destroyed with a few words to a television audience.

The fifth debate should not take place: neither Nixon or Kennedy are likely to make any new points at all, and if they make any more about Cuba or Quemoy-Matsu they will be forming antagonisms, not policies.