SEOUL -- Even as the scope of combat operations in Afghanistan widens and their scale intensifies, the legal basis for waging war under international law grows ever more tenuous. According to U.S. President George W. Bush, the terrorist attacks on the World Trade Center and the Pentagon were an act of war. Similarly, Defense Secretary Donald Rumsfeld and Attorney General John Ashcroft have stated that "we are at war against terrorism" in Afghanistan as well as on the home front.

But war in the material sense is not the same as war in the legal sense. There has been no declaration of war, and U.N. resolution 1368 merely noted the Security Council's "readiness to take all necessary steps" without explicitly authorizing the use of force. Has this first direct attack on the U.S. mainland in almost two centuries obviated the need to seek a firmer legal underpinning for American action in the minds of U.S. policymakers?

By their own actions nations either bend international law to suit their needs or, by strengthening it, render the international order sounder with greater security for the largest number of states. Although consistent with precedent in seeking Security Council support for its action, U.S. reluctance to seek a resolution explicitly authorizing the use of force has unfortunately weakened its case.