The border of the big picture appears to have been completely missed.

True, the project would very likely be an unused piece of American defense, in the "physical" sense. Much like an automated security system programmed to shoot trespassers, but can be circumvented by an aerial assault. The point remains that an enemy would need to expend more energy and money to complete his penetration. To this aim, the current missile defense strategy is completely feasible as a deterrent against potential threats. The enemy would need to work harder, thus running a greater risk of exposing himself.

Dammed expensive, just to force the bad guys to keep up with the Joneses, but if it results in forcing the bad guy’s hand and foils an incredibly deadly scheme, so what? And if it does not -- a scenario we could never be fully aware of anyway -- what does it matter?

It remains that the world is a mess, mainly because of the ignored people within it. Who’s gonna clean it up? I say very likely the nations that can afford to clean it up. Sorry that it just happens to be the world leaders and today’s Allied Coalition of Nations.

Planetary police? Sure, why not?

The short time window available for disabling an enemy missile means that interceptor rockets would have to be based close to enemy territory to have a chance of intercepting the missile in time, if it is possible at all.

Our deep, silent fleet brings the missiles to the enemy's back door, and North Korea, our current “known” nuke-threat, has a very long coastline.

As for the future of missile defense, I will not pretend to know what the next breakthrough technology might be.

Dan