If the United States proceeds with construction of a national missile defense, it could mean the end of an era - the age of mutually assured destruction.
For 40 years, MAD has been the foundation of US security strategy. The Pentagon has structured its nuclear arsenal around the belief that the best way to deter an atomic attack is to ensure that any such blow would be followed by a blistering response in kind.
That cold-war approach won't work as well against the threats of the 21st century, according to defense proponents. They believe that North Korea and other so-called states of concern aren't as predictable, or logical, as the old Soviet leadership.
Critics say that such thinking simply demonizes states that Americans don't understand. If North Korea is irrational, why has the US been negotiating with it for six years to ensure its nuclear program is peaceful?
"Nobody has said that these people don't understand survival," says Jack Mendelsohn, executive director of the Lawyers Alliance for National Security.
The US missile defense effort as a whole faces a crucial test this week. Tonight the Pentagon will launch a mock warhead from Vandenberg Air Force Base in California. Minutes later, it will fire a 130 pound "exoatmospheric kill vehicle" from an atoll in the Pacific about 4,300 miles away. The kill vehicle is supposed to pick out the warhead from a decoy and steer towards a collision. If everything works, a flash in the sky will mark the warhead's destruction and a successful experiment.
If the test goes as planned, President Clinton may order construction to begin on the first phase of a planned $60 billion National Missile Defense (NMD) system. If it fails, NMD critics will surely heighten their criticism - in particular, the charge that with current technology it's almost impossible for the kill vehicle to discriminate a warhead from a decoy.
"The system would offer little protection and would do grave harm to this nation's core security interests," wrote a group of Nobel laureates in a letter to Mr. Clinton this week.
But whether NMD is feasible is only part of the debate about the system that is now roiling the national-security establishment.
In an age when the threat from nuclear-armed superpowers has greatly diminished, and the capabilities of a rocket science have greatly advanced, the deliberate vulnerability that underlies nuclear deterrence has become both avoidable and immoral, say some.
DETERRENCE worked in the past because we understood much about those we were deterring, retired Air Force General Larry Welch told a Senate hearing last week. The US knew what the Soviet leadership valued. US commanders had high confidence that they could hold those assets at risk - and the Soviets knew it.
Such mutual understanding doesn't exist between the US and North Korea, or the US and Iraq, or the US and Iran. If these states of concern (formerly called "rogue states" by the State Department) develop nuclear missiles capable of reaching the US, traditional deterrence may not stop them from pushing the button. "I simply do not know what deters those particular kinds of threats," said Welch.
Even lawmakers critical of the rush toward NMD agreed with Welch that there is an unknowable factor regarding US relations with North Korea or Iran. US intelligence understands little about what motivates their leaders or about their geopolitical goals.
But that doesn't mean deterrence will not keep them in check, said these senators. To call them "undeterrable" is to label them suicidal, madmen, unpeople. "I have no confidence in North Korea either ... all I'm saying is you can't throw out deterrence as a factor even though you don't have as much certainty that it would work with a North Korea...," said Sen. Carl Levin (D) of Michigan.
Pentagon officials deny that NMD, as planned, is aimed at shielding the US entirely from Russia's nuclear arsenal, or even the smaller stockpile of China. For these states, the MAD theory would still hold, they say.
But both Chinese and Russian leaders say they worry any US missile shield would eventually become robust enough to protect the US from their more numerous warheads. From their viewpoint, that would mean the end of MAD - and perhaps a growing fear that the US could strike them with impunity. They warn they would stockpile additional nuclear warheads, perhaps restarting an arms race.
(c) Copyright 2000. The Christian Science Publishing Society