Why care about this eerie bit of nuclear nostalgia right now? Several good reasons: Pronouncements by al Qaeda and North Korea have shattered the notion that there's any sort of "nuclear threshold" that mankind would never dare cross. And America's continuing lack of tactical atomic weapons leaves a major gap between conventional arms and hydrogen bombs - a gap our enemies clearly intend to exploit as soon as they can, robbing us of any chance to deter them or strike back in kind. The idea that the U.S. can somehow save the world by never "going first" with nukes is obsolete, misguided, and naive.

Al Qaeda claims to have nuclear weapons. Military.com carried this in their news headlines on 22 March. The Associated Press was quoting a Pakistani reporter and writer, Hamid Mir. Mr. Mir has written a book about the life and work of Ayman al-Zawahri, reputed to be al Qaeda's second-in-command under Osama bin Laden. Mir quoted al-Zawahri as having stated that the al Qaeda terrorist organization already owns working atom bombs, purchased illicitly in Asia through the underground economy of ex-Soviet weapons technicians. The going rate for a briefcase A-bomb, it seems, is $30 million.

Is this danger to be taken seriously? Intelligence and law enforcement groups have known for more than a decade that al Qaeda has been trying to acquire nukes. North Korea, a country who might by now possess several homemade nuclear bombs, repeatedly threatens to sell some to terrorists. Pakistan's Dr. Abdul Qadeer Khan was unmasked only last month as for years, from sheer greed, having sold bomb-making equipment to Iran, Libya, and North Korea. Al Qaeda operatives, conceivably, might also rank among his customers. And completed nukes, including high-yield hydrogen bombs, have been kicking around the Former Soviet Union ever since the Berlin Wall fell. Extensive, expensive, and shadowy efforts by the U.S. and Russia are attempting to keep those warheads in friendly hands and away from smugglers. (Many warheads have been dismantled, their bomb-grade uranium and plutonium reprocessed into much less dangerous reactor fuel for nuclear power plants.) But borders are porous, security in the ex-USSR is lax, and an all-up bomb or its fissile core might yet appear for sale in some clandestine armaments bazaar. So yes, the danger is ongoing and genuine.

But is al-Zawahri bluffing, in a psychological-warfare gambit aimed at frightening and baiting the West and his other opponents? My personal view is that he is indeed bluffing, at least so far: If al Qaeda really had nukes, they would have proven it by using them already. Up to now, restraint of any sort has not been part of their tactical profile. Transport of the device is not a significant impediment, either. The weapon or weapons needn't be brought into the U.S. homeland, before detonation, to do severe damage. A rogue nuke set off conveniently closer to its (alleged) point of purchase, say in Hong Kong or Bangkok - or even in Afghanistan - would utterly shock the world. Financial markets would dive catastrophically. Fear would rule the minds of voters in nations already subjected to more-conventional methods of terror. And fallout obeys no overflight restriction laws, so a bomb set off on the ground or in a low-flying plane or aboard a ship, and with winds favorable for the enemy's purpose, would shower nearby al Qaeda targets with deadly radiation. Besides mass death in a localized area, the emotional and political impact of one al Qaeda mushroom cloud could shatter the foundations of democracy around the globe. We've seen, in Spain, what ten smallish high-explosive bombs plus some government bungling can do in a presidential election.

Unfortunately, it appears that anti-terror agencies won't get to question al-Zawahri in greater detail very soon. The latest reports say he isn't surrounded in the mountains near the Afghan-Pakistani frontier after all. But his ambitions for al Qaeda to become a nuclear power are perfectly real. Some day, not too far off, he and his cohorts might no longer be bluffing.

U.S. A-bomb fingerprinting capabilities are weak. The scientific skills, and specialized equipment, needed to quickly determine the country of origin of a nuclear bomb that goes off in the atmosphere have atrophied since the Cold War ended. The New York Times on 19 March ran a front-page article on the current situation in this increasingly important black art. It's just now becoming publicly clear that a fallout analysis infrastructure is being urgently reconstituted by the U.S. government. For several years, in fact, in secret, processes have been gradually rebuilt from their low point during the brief and illusory "peace dividend" when the Soviet Union collapsed. The Pentagon, several national laboratories, and university experts are involved in strengthening the tools and know-how needed to start from fallout and debris samples after a nuclear blast, and work backward to deduce the bomb's design and origin.

These efforts are best viewed optimistically in their role as a deterrent. The premise here is that if enemies know a detonated weapon can be traced back to them, and retaliation will be swift and decisive, then they're less likely to seek nuclear arms to begin with and use them against us.

But a lot of progress still needs to be made, and there are serious loopholes in attributing a bomb to a specific perpetrator. A nuke made in North Korea, for instance, sold to al Qaeda, who then arranged for anti-Israel factions to use it on Tel Aviv, leaves a very twisted trail. Would the United States be justified in nuking North Korea's WMD plants in return? Would Israel be justified in nuking a Palestinian area to get at a terrorist mastermind? And if al Qaeda is in the loop but is neither the point of origin nor the agency of final use, how does anybody retaliate in kind against al Qaeda - an entity with no boundaries or crucial center-of-gravity in the military context?

In other words, deterrence in advance by relying solely on fingerprinting after the fact is a leaky sieve on several levels. One crucial missing ingredient is good information on every potential bad actor's weapon design; technical approaches and materials used vary subtly but importantly from country to country and sub-state to sub-state. Right now the needed intelligence database, especially on emerging or improvised nuclear devices and dirty bombs, is far from complete.

Advances on this front are steady but slow, according to one quoted project expert, in part because the mental images conjured up by such work are so very unpleasant. But efforts should be continued and, if anything, stepped up, because even to the least squeamish among us, the consequences of dawdling or failure would be much worse - unpleasant images turn into hellish realities.

Iran and North Korea are still at it. These two rogue nations and state supporters of terrorism either are now, or grow ever closer to being, actual nuclear powers. Nothing in their recent behavior shows any meaningful sign they intend to back down, after years of violating international treaties and ignoring United Nations sanctions. Once a nuclear wannabe regime, it seems, then always a nuclear wannabe regime.

Conclusion. A well-made nuclear bomb, despite popular misconceptions, isn't very radioactive until it explodes. Sneaking one, with modest shielding and camouflage, past the most vigilant border guards is not impossible.

Los Alamos recently announced successfully testing a new technology, which finds uranium or plutonium in a truck or shipping container not by its own radiation but by how these fission-bomb elements (which are also present in hydrogen bombs) interact with cosmic ray byproducts that continually hit the earth from outer space. This equipment shows great promise, but deployment in the field at every border crossing and harbor is years away. Even then, determined terrorists can always try to sneak through where the border patrols or Coast Guard aren't, or can detonate the bomb on the spot if found out.

Prevention thus requires a multi-pronged approach, supported by total national commitment. Aggressive but street-smart human intelligence agents, and Special Forces, are needed to infiltrate thoroughly into enemy cultures on their own turf. Diplomacy must be firm and insistent, with no more nonsense tolerated from treaty-breakers who bob and weave. Cheap but foolproof bomb sniffer gadgets are needed in quantity, ASAP. And deterrents of every type, from fallout fingerprinting to ground-penetrator low-yield nukes that can take out the deepest imaginable hardened bunker sanctuaries, must be part of America's defensive repertoire -- along with the willingness, if need be, to use proportionate armed force, even pre-emptively.

With rogue nukes we can't afford to absorb the first blow as the victims; it's better to take any figurative heat in the form of resentment from third-party countries instead, while we keep our homeland physically safe. Ample stocks of modern tactical nukes in our hip pocket, backed by our existing H-bomb arsenal, should serve as adequate measures to squelch additional flinging nukes, if we're ever forced to retaliate or pre-empt - against fanatics with nuclear weapons they're perfectly willing and eager to use. To let our own worst fears of Armageddon take control, and have ourselves be pushed into a passive, sacrificial posture, is the outcome al Qaeda would most dearly wish. If we're reduced to bringing back duck-and-cover drills as if that's the answer, we as a society are in terrible trouble indeed.

JoeBuff.Com / Joe Buff Inc. Joe Buff, President Dutchess County, New York E-Mail readermail@JoeBuff.Com