I think that the use of nuclear weapons is different than any other form of aggression, because of the results of their only previous use against Japan. We now understand the wide ranging impact. I agree with Doug that the US would never launch an attack. However, the nuclear card was played at least once by the US to force a Russian retreat from Northern Iran shortly after the end of World War 2, to the best of my memory. The potential for Nuclear Blackmail has not existed since the USSR got the Bomb in the early 50s, but with SDI their is certainly potential for return to those tactics.

One thing is certain though. The developed nations of the Earth are far more commercially entwined than they were during the Cold War. Even China, that rogue Superpower, is more interested in the US as a market for their products than as an adversary. I'm convinced that we have much more to fear from the "have nots" of the world, the countries dominated by monomaniac dictators or religious fanatics, than from any other nation who is benefitting from the "global economy". And what should our approach be to the "have nots"? We should combine forces with other developed nations to force compliance to nuclear non-proliferation controls, while emphasizing democratic government and basic human rights. Sound too much like "One World Government"? Perhaps. But the world seems to be drifting in that direction under its own momentum. Why not attempt a consensus on a goal, and not just a direction?

SDI accomplishes nothing except to emphasize a separateness for the US from the surrounding world, a separateness that is fast slipping away since the Cold War's end.