It was literally, as well as figuratively, heated. When Mr. Kendall noticed the Soviet leader wiping his brow, he rushed over with a nice cold Pepsi and was rewarded with a unique, unpaid commercial for his product, published round the world. Mr. Kendall followed up with a deal obtaining exclusive rights to the Soviet market in return for exclusive distribution rights for Stolichnaya vodka in the U.S.

But the American vodka market has limits. So later Mr. Kendall began looking for other Soviet products he could sell to remit Pepsi's ruble earnings. Thus the tanker and the castoff fleet. The Pepsi monopoly in a vast country has given heartburn to the Coca-Cola people. In what he calls ''the cola wars,'' the international lawyer Sam Pisar got special rights for Coca-Cola to supply the 1980 Moscow Olympics, as it had every Olympics since 1924. But it refrained because of the American embargo on the Games after the invasion of Afghanistan.

Since then, Coca-Cola has introduced some other lines to the Russians, such as Fanta and Minute Maid, with special deals for repayment. But real ''Coke'' can still only be bought in special hard-currency stores for foreigners.

Coca-Cola's resentment may explain a recent nasty column by William Buckley, normally no enemy of business initiative, wondering if Mr. Kendall ''has put in for Pepsi concessions in the gulag'' and noting tartly that ''as sales of Pepsi mounted, so did the creation of nuclear missiles'' in the Soviet Union. It takes a lot of fantasy to make an American soft drink responsible for Soviet forced labor and atomic weapons.

On the contrary, it would seem that winning Russian gullets, and maybe hearts and minds, with American consumer products is all to the good for both sides. Apart from specific goods with military applications, it makes no sense to brand trade with the Soviets as some kind of greedy treachery.