It is time once again to quote my favorite philosopher -- Tevye, the lead character from "Fiddler on the Roof." It was his habit to weigh his options by saying, "On the one hand, " and then, "On the other hand," until he confronted a situation where there was no other hand. This is where Colin Powell brought us all yesterday.

The evidence he presented to the United Nations -- some of it circumstantial, some of it absolutely bone-chilling in its detail -- had to prove to anyone that Iraq not only hasn't accounted for its weapons of mass destruction but without a doubt still retains them. Only a fool -- or possibly a Frenchman -- could conclude otherwise.

The clincher, as it had to be, was not a single satellite photo or the intercept of one Iraqi official talking to another. And it was not, as it never could be, the assertion that some spy or Iraqi deserter had made this or that charge -- because, of course, who can prove any of that? It was the totality of the material and the fact that Powell himself had presented it. In this case, the messenger may have been more important than the message.

This time, for instance, when the by-now hoary charge was made that a link existed between al Qaeda and Baghdad, it was Powell who made it -- and it hit with force. This time, when it was said that Iraq had developed unmanned airplanes that could dispense chemical or biological agents, it was Powell who made the charge -- and showed a picture of one. This time, the finger-pointer was the man who, heretofore, had been accused of what in the Bush administration is a virtual slander: prudence. Here was a reasonable man making a reasonable case.

To my mind, Powell's most compelling statements came when he acknowledged doubt or differences of opinion. He did so when discussing Iraq's importation of aluminum tubes that Baghdad may -- or may not -- be using as centrifuges for enriching uranium.

"By now, just about everyone has heard of these tubes, and we all know that there are differences of opinion," he said. "There is controversy about what these tubes are for." You bet, and saying so enhanced his credibility.

If Powell failed in any area it was in proving that Iraq has a nuclear weapons program that poses an imminent -- or even proximate -- threat. That appears not to be the case. Its program seems no different from those of many other nations -- although its ultimate intentions are a far different story. If it could get fissionable material it would undoubtedly make a bomb. But it's apparently not at that point yet -- or even close to it. (It's almost impossible to hide a true nuclear weapons program.)

This is not a minor point. The Bush administration consistently cited the Iraqi nuclear weapons program as the ultimate reason to change the regime in Baghdad. It seemed then -- and it seems now -- an exaggeration. It has cost the administration some credibility.

But the case Powell laid out regarding chemical and biological weapons was so strong -- so convincing -- it hardly mattered that nukes may be years away, and thank God for that. In effect, he was telling the French and the Russians what could happen -- what would happen -- if the United Nations did not do what it said it would and hold Saddam Hussein accountable for, in effect, being Saddam Hussein.

The French, though, are so far deaf to such logic. Their foreign minister, Dominique de Villepin, said that the consequences of war are dire and unpredictable. He is right about that. But the consequences of doing nothing -- and mere containment of Iraq amounts to nothing -- are also dire and somewhat predictable. The United Nations will be revealed as a toothless debating society -- a duty-free store on the East River -- and every rogue will have learned a lesson from Saddam Hussein: Stall until everyone loses interest.

North Korea probably already has nuclear bombs. Iran may have a nuclear weapons program. Pakistan has the bomb, India and China too. All kinds of states -- stable, unstable and just plain nutty -- are making weapons of mass destruction. Pretty soon, any collection of fanatics with a chemistry set will pose a horrific threat. The world is steadily becoming less and less secure. Now is not the time for the United Nations to flinch.

As with Tevye, there is no "other hand" when it comes to Iraq. If anyone had any doubt, Powell proved that it has defied international law -- not to mention international norms concerning human rights -- and virtually dared the United Nations to put up or shut up. There is no other hand. There is no choice.