PERSPECTIVE ON IRAQ : Saddam’s Secret Stash Is Nuclear : He may give up Scuds in his game of cheat and retreat, but the big prize may escape detection despite a wealth of clues.

Iraq’s “good-faith gesture” to raze its Scud missile works is just one more example of Saddam Hussein’s survival game: cheat and retreat.

Iraq’s apparent capitulation to the United Nations on Friday ended a 10-day diplomatic offensive. Arguing Iraq’s case before the Security Council, Deputy Prime Minister Tarik Aziz skillfully implemented Hussein’s basic game plan for emerging as as the long-term victor in the Gulf War: Split the coalition against Iraq; convince some Security Council members that there is ambiguity or unfairness in the resolutions ordering Iraq to forswear all weapons of mass destruction; get some relief from the sanctions enforcing those resolutions, and dispense with the pesky inspectors swarming over the Atheer and Tuwaitha nuclear weapons plants.

If this strategy works, the world is likely to have a new member of the nuclear missile club in short order. And we will not know if the strategy has failed until the head of the U.N. Special Commission on Iraq, Rolf Ekeus, announces that all of Iraq’s unconventional weapons facilities have been destroyed--and that he is confident none remain hidden.

Discussions with past and current members of the U.N. inspection teams have convinced me that as much may remain undiscovered in Iraq as has been unearthed. The Iraqi nuclear weapons program was nearly as broad in scope as the Manhattan Project. Iraqi scientists tried almost every known means of uranium enrichment and succeeded with several. From the beginning, they knew how to build an implosion bomb, and their preliminary experiments at the Atheer weapons lab were successful. The only missing component is a nuclear reactor to make plutonium, which is easier to use in an implosion device than uranium.

As Iraq learned when the Israelis bombed the Osirak plant in 1981, reactors are hard to conceal--if built above ground. A plutonium factory constructed below ground, somewhere along the industrialized Tigris valley, however, might have escaped detection.

Many investigators feel certain that Saddam Hussein does, indeed, possess a reactor for making bomb-grade plutonium and has hidden it well. They, and I, believe that if the Iraqis did build a reactor, it was shut down in order to escape the eye of the U-2 spy plane thatthe United States has provided the U.N. Special Commission inspection teams. The regime would go to any length to preserve such a jewel for use once inspections cease.

And that is the problem. A certain amount of fatigue seems to be setting in among the inspectors and those who must pay their political bills. Too often they have drilled into the clay of Iraqi obstinacy and obfuscation, only to leave dry holes behind. One hunt for the reactor failed, and now there seems to be less interest in looking for other sites.

The crack of disunity that Tarik Aziz exploited at the United Nations this month is likely to grow in the absence of new discoveries, and given the existing conflict of members’ agendas, there may not be political will to support the kind of aggressive monitoring that will produce results from the field.

But the information already extracted from the close-mouthed Iraqis is enough to justify the continuous presence of a U.N. inspection force for at least a decade. Every page of every inspection report is replete with information on hardware that has its most probable use in a nuclear weapon, a chemical weapon or the missiles to launch them.

At Atheer, the inspectors found a control bunker with electronics “over-designed for their declared use,” the testing of conventional bombs. The bunker itself was over-designed and equipped with the instruments needed to prove out the operation of a nuclear detonation system.

At Qa Qaa, the Iraqis had built detonators that were unavailable on the world market but were precisely what is required in a nuclear device. They claimed that the high-tech detonators were for a space launcher, but the explosive system was to be accurate to one-half-millionth of a second, an extreme over-design for space but required for a nuclear weapon.

During the Gulf War, it was believed that the Iraqis extended the range of their Scud missiles by taking three Soviet-supplied rockets, cutting the tanks out of one and adding those cannibalized sections to the other two. We thought the Iraqis were in a two-for-three trade-down, gaining range but losing firepower. Today we are fairly certain that the Iraqis made the sections themselves; they didn’t have to trade quantity for quality.

The coalition triumphed in the desert a year ago, but it will have won no lasting victory if the entire Iraqi special weapons infrastructure is not sought out, found and destroyed. If the microfilms of the documents remain unburned, if the bunkers remain unshattered and the labs undestroyed, and if a nuclear reactor remains hidden for later use, the Iraqi war machine will soon be back, more completely armed and more ferocious than before.