WASHINGTON -- What can they be teaching in American law schools today about the principles of international law and constitutional law now that our nation is practicing "unilateralism" and "preemption?"

Is it a case of "do as we say, not as we do?"

The U.S. invasion of Iraq flouted many of the legal commitments and treaties that we have pioneered and fostered since World War II.

The United States also has conveniently skirted the United Nations charter, which limits the legality of taking up arms against another country to instances of self-defense or when the U.N. Security Council has given its prior approval.

So why haven't we heard more from leaders of the legal community? The 9-11 terror attacks seem to have thrown them for a loop.

Harvard law professor Alan Dershowitz went so far as to call for "torture warrants" under which courts would authorize the use of force to extract information in extreme situations. I'm happy to say that suggestion was roundly condemned.

Most of the war-ridden 20th century pointed to the need for collective security and global organizations to combat aggression. That move toward international cooperation was a huge leap from the super nationalism so rampant in the 1930s that spurred the European "isms" of fascism and communism.

Those agreements would not have come about without the strong commitment of presidents like Franklin D. Roosevelt and the efforts of internationally-minded public servants.

Had it not been for our country -- which abandoned isolationism during World War II -- there would have been no United Nations, no NATO and probably no European Union.

Since we now have chosen to ignore the will of the U.N. Security Council and the wishes of most of the members of the world organization, the relevancy of the United Nations is being questioned by those who scoff at the moral authority of the world body.

American critics of the U.N. seem to be saying that the United Nations is only relevant when it follows our orders and when it gives us a blank-check endorsement of our policies. Otherwise, we won't play.

Of course, some conservative groups have never accepted the authority of the United Nations, relegating it to an impotent debating society, except when we needed it as window dressing or when its policies agreed with ours.

If we spurn such international organizations and embrace the theory of unilateralism -- the concept that we are in charge and can call all the shots because of our military dominance -- we will undoubtedly reap a legacy of hate.

Because of our defiance of international law, our nation also will fall from its pedestal as a great moral leader to the world. We will be feared -- but we will no longer be revered.

Meantime, we do not know what will be the impact of the new aggressive unilateral U.S. foreign policy on international economic and monetary organizations such as the World Bank, the International Monetary Fund and the World Trade Organization.

But we do know prosperity and trade depend on the confidence and trust between nations and how they get along in the global political arena. They are not mutually exclusive.

Now that we are bypassing the tenets of international law and acting out our own rules of behavior on the world stage, I pity the professors in the law schools. Their challenge will be to explain how our nation, which prides itself as a nation of laws, got itself into this fix.

(Helen Thomas can be reached at the e-mail address helent@hearstdc.com)