PRESIDENT REAGAN traveled through a Western Europe whose sleek prosperity makes it hard to remember the chaos and destitution there four decades ago. This trip was an occasion for much recollection of victory. But it is also useful to remember the postwar years, when people literally starved to death in Europe. In his memoirs Gen. Lucius Clay, the American commander in the occupation of Germany, included a photograph of a child dying of malnutrition in a hospital crib; the picture is juxtaposed to another of a lavish meal in a black market night club. In northern Italy, for months after the German surrender, a covert civil war raged savagely between right and left. In early 1946 Gen. Charles de Gaulle resigned in a huff as provisional president of the very new Fourth Republic, and for a time it seemed unclear whether France could construct a regime that was both democratic and capable of governing.

The images of present Europe are so strong in everyone's mind that even historians -- who ought to know better -- sometimes wonder whether it wasn't inevitable that Europe would divide down the middle into Russian and American spheres, and that the Americans' half would grow rich. But nothing was inevitable in 1945, or the several years that followed. Europe seemed trapped in self-perpetuating cycles of violence and, just as the second world war had often paralleled the course of the first, the early postwar years were unpleasantly reminiscent of the poverty and bitterness of 25 years before. One new element was active subversion by communist movements under the direction of the Russians. It was an open question whether, once again, democracies would not weaken and collapse under challenge.

The rebuilding of Europe was above all else a feat of moral courage -- a display on a historic scale of the vitures of magnanimity, generosity and faith in the future, some of it contributed by Americans but much of it by the Europeans themselves. The late 1940s and early 1950s were a remarkable time in which Europeans came to realize that they were drifting in the same tragic pattern as a generation earlier and, by an enormous exertion, like swimmers fighting their way free of an undertow, carried themselves and their countries in an altogether new direction.

The Europe that Mr. Reagan visited is serene, stable and even a bit dull in its politics. That prosperous dullness reflects a triumph of statecraft over these 40 years. Among the victories being celebrated this year, the victories of the postwar politicians deserve to be remembered with special gratitude.