War, like other things, can have different costs at different times.

Winston Churchill once argued that Hitler could have been stopped at far less cost in human lives if the Western democracies had acted earlier. At one very early point, Churchill said, Hitler could have been stopped by a memorandum. Instead, the West waited until the eleventh hour, barely escaped losing the war, and ultimately expended millions of lives to win it.Some people resist the comparison between Saddam Hussein and Adolf Hitler, not on moral grounds, but because Iraq is not considered to be the military threat that Nazi Germany was. However, just four years before World War II began, Hitler's military forces were far less formidable to his neighbors than Iraq's forces are today.

That was the point at which Hitler could have been stopped by a memorandum.

If war with Iraq is inevitable, it will probably cost fewer lives if it happens sooner, rather than later. No one knows whether it is inevitable, or would have been if the United States had made no response to the invasion of Kuwait.

But the track record of Saddam Hussein does not make it hard to imagine where he would be in a few years, with the oil riches of Kuwait and additional wealth extorted in one way or another from the other oil-producing states in his vicinity.

That could buy a lot of missiles, with ever-longer ranges, and more warheads with chemical, nuclear and biological weapons. As for the comparison with Hitler, even the Nazis held off using poison gas against the Allied nations in World War II because they had been warned that this would bring retaliatory gas attacks on the German people.

It is doubtful whether any such threat against the Iraqi people would deter Saddam Hussein. It is also questionable whether any economic pressure against the nation of Iraq will induce Saddam Hussein to surrender power. It may turn out to be optimistic even to hope that economic sanctions will accomplish the official aim of the U.N. military intervention in the Middle East - that is, to force an Iraqi withdrawal from Kuwait.

But suppose that it does succeed in that aim. Will that be a successful conclusion of the matter, with American (and other) troops going back home in triumph? Saddam Hussein would have succeeded in looting and perhaps fatally disrupting Kuwait as a viable independent nation. More important, both his added economic resources and his enhanced political reputation throughout the Middle East would make him a bigger and more dangerous threat than ever.

Let us push the optimistic scenario a step further. Suppose the U.N. forces Iraq to pay reparations to Kuwait and the Kuwaiti government returns to unscramble the population so that the original Kuwaitis regain their homes and expel from the country all the other people whom Saddam Hussein has installed there.

Will even that be enough to reduce the Iraqi threat for the future? Or will it merely feed the desire for revenge by Saddam Hussein?

If even these optimistic scenarios seem to leave the prospect of a bigger and worse war in the future, there may not be a real alternative to a decisive war in the present. Perhaps, as some new-isolationists have been saying, we would have been better off to have stayed out of the Middle East militarily, because oil is not worth blood and we cannot be the world's policeman.

But that is no longer an option. You cannot un-ring the bell.

If in fact the only real solution of the Middle East crisis is to remove Saddam Hussein from power and destroy Iraqi's warmaking potential, as was done with Germany and Japan after World War II, then it may be understandable why the president has not - and could not - "explain why we are in the Persian Gulf," as so many critics have demanded in the media.