Senator Levin’s amendment called for United Nations approval before force could be authorized. It was unambiguous and compatible with international law. Acutely cognizant of the dangers of the time, and the reality that diplomatic options could at some point be exhausted, Senator Levin wrote an amendment that was nimble: it affirmed that Congress would stand at the ready to reconsider the use of force if, in the judgment of the president, a United Nations resolution was not “promptly adopted” or enforced. Ceding no rights or sovereignty to an international body, the amendment explicitly avowed America’s right to defend itself if threatened.

An opponent of the Levin amendment said that the debate was not over objectives, but tactics. And he was right. To a senator, we all had as our objectives the safety of American citizens, the security of our country and the disarming of Saddam Hussein in compliance with United Nations resolutions. But there was a steadfast core of us who believed that the tactics should be diplomacy and multilateralism, not the “go it alone” approach of the Bush doctrine.

Those of us who supported the Levin amendment argued against a rush to war. We asserted that the Iraqi regime, though undeniably heinous, did not constitute an imminent threat to United States security, and that our campaign to renew weapons inspections in Iraq — whether by force or diplomacy — would succeed only if we enlisted a broad coalition that included Arab states.

We also urged our colleagues to take seriously the admonitions of our allies in the region — Egypt, Jordan, Kuwait, Pakistan, Saudi Arabia and Turkey. As King Abdullah of Jordan warned, “A miscalculation in Iraq would throw the whole area into turmoil.”

Unfortunately, these arguments fell on deaf ears in that emotionally charged, hawkish, post-9/11 moment, less than four weeks before a midterm election. The Levin amendment was defeated by a 75 to 24 vote. Later that night, the Iraq War Resolution was approved, 77 to 23. It was clear that most senators were immune to persuasion because the two votes were almost mirror images of each other — no to the Levin amendment, aye to war. Their minds were made up.