Among the many pieces of unfinished business from the Iraq war, one in particular threatens future global security. Inexplicably, Iraq is to this day a signatory in good standing of the nuclear Non-Proliferation Treaty. If it remains so, the treaty will become a worthless sham. If that were to happen, not only would nuclear containment be mortally wounded, so would efforts to control the other means of mass destruction: chemical and biological weapons and the ballistic missiles to deliver them.

Released from its siege in the parking lot, the U.N. nuclear inspection team described the evidence of flagrant, wholesale and continuous violation of the intent of the Non-Proliferation Treaty by Iraq stretching back for more than a decade. What was implicit and suspect before is now laid out in terrifying detail. Not the most cautious diplomat nor the most timid international organization can any longer look the other way.

Since preempted by Israel's 1981 bombing raid from producing its own plutonium, Iraq has pursued not one, but three, secret programs for making highly enriched uranium, the other nuclear fuel. The inspectors found that Iraq had neutron initiators, high-explosive lenses, electronic firing sets, computer codes and the other assorted paraphernalia needed to make a nuclear bomb. Except for sufficient fissile material, said the U.N. team leader, "on every other front Iraq had ... a workable solution." It had even begun to work on the hydrogen bomb.

The international response so far has focused on discovering and destroying Iraq's facilities and on identifying and exposing the companies and countries that provided assistance. While both are necessary, what was built once can be rebuilt, and tighter export controls, though essential, cannot be made leakproof. The less glamorous but vital task is to repair the damage Iraq has done to the international nuclear control regime and then to strengthen it.

Iraq's nuclear intentions were known long before the gulf war. Beginning in 1976 it bought or secretly tried to buy items whose likely or only use was in a weapons program. These included a suspiciously large research reactor, reprocessing facilities to separate plutonium and large amounts of natural and depleted uranium for use as a plutonium source.

Technically, none of these activities violate the NPT. Throughout the '80s, Iraq accepted International Atomic Energy Agency (IAEA) safeguards and allowed twice yearly inspections of its publicly acknowledged facilities. Without recourse to higher authority, and with some reason for believing that Iraq was less of a threat inside the arms control system than outside it, the IAEA did the best it could -- which wasn't much. Both sides persisted in the deceit for a decade. Though there was every reason to believe that Iraq had abandoned its treaty pledge "not to manufacture or otherwise acquire nuclear weapons," there was no proof. Now there is.

The 1968 Non-Proliferation Treaty offered countries only two incentives to renounce nuclear weapons. Explicitly, it promised special cooperation by the nuclear states in peaceful uses of the atom. Implicitly, it offered the hope that by joining the non-proliferation regime, each country would make itself safer by contributing to the collective action.

In the 23 years since the treaty was drafted, special cooperation has proved illusory. The bright promise of nuclear energy has dimmed, and the hoped for uses of "peaceful nuclear explosions" (for massive construction projects) have vanished. All that is left is the treaty's role in stemming proliferation. If that system -- the treaty and the rules, safeguards and inspections built upon it -- not only fails but is unable even to acknowledge and react to its failure, it will stand revealed as a Potemkin village.

If, instead, the 140 parties to the NPT wish to see its promise fulfilled, the first step is to expunge Iraq from their ranks and kick it out of the IAEA. (The legal basis for this lies in the Vienna Convention on the Law of Treaties.)

The next step is to amend the treaty to correct two glaring flaws. The NPT's central prohibition only covers "nuclear weapons or other nuclear explosive devices," which means that members can legally do everything in a nuclear weapons program lasting for years except the last step of assembling a weapon, which takes a few weeks. Also, the treaty's stricture against assisting would be proliferators does not apply to non-nuclear- weapons states, allowing countries such as Switzerland that blink at weapons-related exports, to continue unconstrained.

The IAEA's membership must give it the power to protect their interests through the right to make surprise inspections and to refer suspicious behavior to the Security Council. A system of multilateral sanctions must be developed that would apply a real price to any country that acquired nuclear weapons inside or outside the NPT. The unilateral U.S. sanctions that cut off economic and military assistance are the starting point.

Successful regimes need inducements as well as credible sanctions. Non-proliferation is its own reward: India and Pakistan, each now nuclear armed and less secure than it was before, stand as testimony to that truth. Something more may be needed, however, to replace the elapsed promise of nuclear cooperation. Some types of international assistance, to take one example, could be tied to the renunciation of all weapons of mass destruction.

This is, granted, a daunting diplomatic agenda. Only one thought makes it seem worth trying: Suppose Saddam Hussein had been patient enough to wait a few years before invading Kuwait. There are other governments like his waiting in the wings.

The writer, vice president of World Resources Institute, writes this column independently for The Post.