The president will spend Thanksgiving in the desert. So will Americans, some 240,000 of them - as part of a unit instead of a family.

There will be letters from home and reports for the television cameras. Some of the soldiers will even unwrap holiday gift baskets full of bubble gum and Cracker Jacks and Jucyfruits, as if the soldiers were kids at camp.All these signs tell us that we are at war again. Not war in the sense of fighting and dying. Not yet. We are at war in the sense of families separated, daily lives disrupted. This is not new to us. The Thanksgiving image most imprinted in our national memories was done when we were at war. It was 1943 when Norman Rockwell painted his family dinner to illustrate Roosevelt's "Freedom from Want."

But that Thanksgiving Americans knew what we were doing abroad. That year, home was really the home front. During World War II, our self-image was of a peaceful people driven to combat.

What has changed most in this half-century? Today, when the president talks about defending "our way of life" we don't visualize four freedoms but great tankers of oil. At home, we are not called on to ration gas but expected to use it at will. There is no Pearl Harbor to remember.

What has changed most? Today, our troops are volunteers, professionals. Out of every 100 recruits, 10 sign on "to serve their country," 39 for college money, 26 for a job or job training.

Ask them what they are doing in Saudi Arabia on Thursday, and most will say they are doing their job.

Finally, what has changed most? Americans are no longer seen as the world's liberators. Indeed, we may be becoming its mercenaries.

In this "international" effort, the world has deplored Saddam Hussein. But we have deployed the troops. The British have offered the fiercest fighting words. But only 16,000 soldiers.

The Kuwaitis have given us the reason to fight. But only 3,000 fighting men. The Japanese allotted $2 billion with strings attached. But no soldiers.

We are in this "together." Some 240,000 American troops and some 450 Canadians. There is, it appears, unified world opinion that WE should stop Saddam. Along with the Saudis, it is our show, our $80 million or more a day, our men and women.

After half a century of war and cold war, of military actions and buildups, I am afraid that conflict has become our specialty. Japan makes cars. France makes fashion. Korea makes televisions. We make wars. Wars 'R' Us.

I do not say this as a pacifist, although I have grave misgivings about this Desert Shield adventure. There are just wars and just causes. The world has reasons to stop aggression.

But we have come to assume the job as international cop, and the rest of the world has come to depend on us as good cop and rail against us as bad cop. We have sadly staked our last, lingering claim to be No. 1 on the battlefield.

If Saddam is "another Hitler," if Iraq is close to having a nuclear weapon, then it is not only our cause for alarm. If we are merely alarmists, there is no reason to go it alone.

When the world looks casually to America for a low-cost protection, an international security system, it is time to prick the balloon of that fantasy. This is not how we see ourselves.

We are not the world's mercenaries.