THAT AN OFFICIAL of the Federal Republic of Germany was sacked last month for comparing George W. Bush to Adolf Hitler was proper, but not because of the insult to Bush. The extremity of Hitler's malevolence must always be insisted upon. Whatever one's problems with Bush, it banalizes evil to equate him with the author of the Final Solution. Germans must be particularly careful not to do this.

Historical analogies can often mislead, as the numerous dead ends beyond the signpost of ''appeasement'' show. How many people have needlessly died in the name of avoiding another Munich? But humans are nevertheless condemned to understand the present in the light of the past, especially when events seem unprecedented. It is clear that, with the American president intent upon a new program of moralistic imperialism, beginning with a war in Iraq, we are in what might be called a threshold period, leading from one conception of society to another as yet undefined one. The ominous situation requires us to ask: When have we stood in such a threshold before?

For Americans of my generation, the years between 1963 and 1965 leap to mind. It was then that decisions taken in Washington established a momentum of violence that ran unchecked for a decade. By the time US citizens realized what was being done in their names, it was too late to stop the momentum until it ran down on its own timetable. The United States after the war in Vietnam was a very different place from the United States before - to say nothing of the transformation of Vietnam. A historic threshold had been crossed, but what everyone saw by 1975, few had seen in the pivotal period of 1963-65.

What characterized that threshold? Four things:

Low-grade social panic. American citizens had just suffered through two traumas - the near-apocalypse of nuclear war over Cuba and then the shattering of national self-confidence with the assassination of President Kennedy.

The mainstreaming of previously ''extremist'' ideas. Lyndon Johnson was elected in 1964 as the ''peace candidate,'' but he immediately embraced the rampant belligerence of Barry Goldwater. Savage violence was promoted with hyper-rationality as the ''moderate'' course.

The surrender by legislators of their constitutional authority. Congress ceded emergency powers to the executive with the Gulf of Tonkin resolution, and political opposition to the war was permanently marginalized, from Gene McCarthy to George McGovern.

The recasting of patriotism to mean conformity. National self-criticism was defined as disloyalty. America - love it or leave it.

To list such defining notes of a threshold period in the past is to recognize them in the present. Our social panic today is tied to terrorism. Formerly extreme ideas (contempt for the UN, unilateralism, carelessness about civil liberties) animate Washington now. The US Congress has just given Bush nearly unrestricted license to use force. Citizens are detached, dissenters are marginalized, and a momentum toward permanent war is set loose.

But even to enumerate such characteristics of the time is to recall another threshold period, one to which we must return again and again - but this act of memory can seem offensive for a reason already noted. Between 1933 and 1935, the world changed, although how it changed was not clear until the horrible decade that followed had run its course. The notes of that threshold period are familiar. The 1933 social panic in Germany was tied to economic distress and to active dread of terrorism - in this case communist terrorism (Hitler was elected on March 5, just days after the Reichstag was burned, a national horror blamed on communists). The once widely denounced ideas of Nazism, especially the political exploitation of anti-Semitism, quickly found a place in mainstream attitudes. (Few objected to the Nazis' April 1 offensive against Jews.) German legislators ceded their responsibility to Hitler by passing the ''Enabling Act'' in April. The last opposition party - the Center Party - dismantled itself. The broad population of Germany quickly accommodated the new hysterical nationalism despite excesses few would have affirmed earlier. A threshold was crossed.

The point of this analogy is not to compare Hitler to Bush any more than the 1963-65 analogy is to compare Johnson to Bush. The question is not about leadership but about societies that allow themselves to be radically transformed without substantial debate. The question is about what is lost when traditional restraints are abandoned and about what follows when the momentum toward open-ended war is set loose. The question is about the cost of world-primacy ambition and who pays it. The question is about what happens when national consensus is hijacked by fringe politics and when the very people empowered to object say nothing. The question, in other words, is not about Bush but about us.

James Carroll's column appears regularly in the Globe.

© Copyright 2002 Globe Newspaper Company

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