It is in obedience to human nature and the imperatives of politics that Ronald Reagan and Mikhail Gorbachev have both engaged in some discreet doctoring of the credit lines for the great defeat of Hitler 40 years ago. But as some Europeans with long memories must ruefully reflect, it is a dangerous game for any player.

In Gorbachev's V-E anniversary speech to the Supreme Soviet, he heaps blame for Hitler's rampage primarily on "the Munich collusion," his term for what is known to our history books as the Munich agreement. Munich was the 1938 centerpiece of Neville Chamberlain's appeasement policy. It permitted Hitler to grab the German- speaking parts of Czechoslovakia without a fight, in the hope that this concession would sate his territorial appetite.

It did not. But in Gorbachev's doctored version, Munich is treated not as an act of folly by the democracies, but as a scheming attempt by "monopoly capital" to deflect Hitler's aggression eastward (though, as "Mein Kampf" had already made clear, he needed no such deflection).

What Gorbachev omits, moreover, is that a year later, in 1939, Stalin and Hitler agreed in the Molotov-Ribbentrop Pact to an armed truce at Poland's expense. Munich may have been a prelude to war, but the war started only after the Hitler-Stalin accord secured Hitler's eastern flank and enabled him to maraud Western Europe unmolested.

This is one of those essential pieces in the historical fabric of the 20th century that young Russians apparently aren't allowed to hear much about. But then young Americans won't learn much about our own contributory negligence in the origins of World War II from Ronald Reagan's Camelot-like picture of U.S. behavior and intentions.

The United States did nothing in the 1930s so criminally negligent, so contributory to the Nazi delinquency, as the Hitler- Stalin pact. Our venial sin of omission was a sanctimonious standoffishness from the European balance of power. We detached ourselves from it with the usual claim that it was the reward of historical innocence.

But this claim to innocence was almost as phony and self-deceiving as Gorbachev's doctored view of Munich.

We had already involved ourselves irretrievably in the destiny of Europe by entering World War I in 1917. Once we had plunged into that conflict, in the name of the rights of neutrals, we contributed our share to the destruction of the old European state system.

In its place President Wilson offered the intoxicating idea of "self-determination," which seemed to imply that every linguistic culture deserved a country of its own for that reason, if for no other. And having introduced this exhilarating novelty, we became disillusioned at how hard it was to work out its practical consequences. We came home and slammed the door.

But as Lincoln had warned us in another time, "We cannot escape history." History caught up with us again at Pearl Harbor in 1941 and before that in the mortal peril of Great Britain. The knock on the door came on the other side of the world, however, and we can only wonder what Congress (having just renewed the draft by one measly vote) would have done about Hitler's war at even that late hour had Hitler not settled the issue by declaring war on us.

The old newsreel scenes that American children, and no doubt Russian children too, have been seeing in recent days are all memorable. None is so memorable as the scene of doughboys and Ivans embracing by the Elbe 40 years ago. But the history leading to this scene was more tangled than they suspected. Those boys who crushed Hitler at such cruel cost were the real heroes of World War II. But most of them probably hadn't the foggiest idea of the flights from responsibility by their elders and leaders that had permitted Hitler to get his hand at the throat of civilization.

They deserved better, just as their historyless children and grandchildren deserve to know more about the crucial things Reagan and Gorbachev omit from their celebratory speeches.

There's always credit to go around in a victory celebration. The more instructive and useful remembrance, however, is who let things get so far out of hand in the first place, and why. If the truth be told about the failure of a timely check to Hitler, neither the United States nor the Soviet Union would escape whipping.