The question of missile defense isn't really wether or not we should try and defend ourselves (I hope the answer to that is obvious), but whether or not it is actually feasible. First of all, any nuclear warheads that are coming toward the mainland US are going to be extremely advanced. We're talking, most likely, shit from Russia or China (and perhaps in a decade or so from North Korea). Typically a ballistic missile will carry multiple nukes (I believe in a range of 5 - 10, but "multiple" is the operative word here). Also, they will be carrying a number of decoys as well. As of 2001, the most sophisticated anti-missile technology could not distinguish between the actual nuclear bombs and the decoys. This means that inorder to even hope to take down one rocket's worth of bombs, we'd have to send like 20-30 anti-nuclear missiles.
Then comes the question of detonation. There are really only two feasible methods of disarming incoming nukes as of the last time I read up on the issue. One is my detonation with a warhead of our own. The other method utilizes an EMP to disable the tech onboard the missile and warhead, thus turning the entire thing into a giant, flying paperweight. The problem with the EMP approach is that what goes up, will obviously come back down and the question is, where? Great, so know we've saved millions in a major metropolitan area while leveling half a city block with the reckage and in turn we still have to recover the Uranium/Plutonium to make sure that we don't have radiation issues. Try running that one past the public. "Sure, ladies and gentlemen, it could be YOUR house that gets a nuclear warhead as an uninvited house-guest, but I assure you, it is completely harmless." So then we look at the other option, remote detonation. Well, it we detonate it too close, sure we can avoid the blast, but now we just multplied the area of effect of the radiation ten-fold. Ok, well the easy solution to that is to blast these things as close to enemy territory as possible. I'm going to go ahead and gloss over the fact that it would be nearly impossible to detect a missile launch early enough to detonate overhead of the enemy country and just get to the ballistics/foreign relations issue. Imagine that we are worried that a country is going to shoot nukes at us, so we put in place anti-nuclear defense. Well, if we want these nukes to be remote detonated as close to their territory as possible, we will be using rockets with a ballistic range capable of hitting their country. Now, these rockets will always be aimed at said country to minimize response time in case of an attack. Well, these are the same kinds of missiles that they are aiming at us, only for some reason they´re supposed to actually believe us when we say that they aren't carrying a payload of nuclear weapons. What do you think they're really going to think? Wait... Isn't this how the Cold War started?
