A colloquy which had partial New Yorker appearance in which Whitworth, a layman, and anything but naive--he's logical, persistent and highly conversant with much that has been said and written about why we are in Vietnam--questions Eugene V. Rostow. Professor Rostow of Yale was deliberately chosen as a former member of President Johnson's administration (Under-Secretary of State for Political Affairs) to explain, viz. defend, the policy not on a moral or military but geopolitical level. Rostow sidesteps much of Whitworth's hypothecating interrogation and in general retreats to uphold the balance-of-power concept (we have to have the balance to protect our interests and we have to protect our interests to protect the balance--indeed ""the tiger is eating its tail""). In fact he cannot be dislodged from this position even where Whitworth limns a little ""scenario"" (Rostow's word) of what really would happen if we did not retain Japan as an ally, if we conceded all of Asia, and if we wrote off the fear (an irrational fear--Whitworth) of Asian hegemony while necessarily maintaining the standoff in Europe with Russia which we have been able to effect. And what of nuclear deterrence? Are we really any safer from China alone than China and Japan in consortium? Although Professor Rostow does most of the talking (and theorizes--""all politics is a function of extremely complex variables which have different weights"") Mr. Whitworth is the conclusive winner. In fact at one point Professor Rostow says--""your argument is really too logical.