Interesting.
At the risk of sounding alarmist, I think it's funny how most people believe that when the Cold War "concluded" so did the threat of nuclear war and/or disaster (and all the horrifying scenarios that go along with both) when the reality is that the threat is even more prevalent now. That being said, I don't fear nuclear war simply because the lunacy of M.A.D. and E.L.E. scenarios are such strong deterants- even for despots, crazed military leaders and depraved terrorists. The stockpiling and proliferation of nukes, biochemical agents, espionage and ilk are just apart of one big, complicated pissing contest. The real threat is oil.

I know it's not popular, but I actually LIKE the idea of orbital missile interceptors. Tactical nukes will always be slower than the most recent interception technology, even if the nukes are also in orbit, so I think an interceptor system could actually discourage further reliance on ICBMs and whatnot. Orbital interceptors also potentiate intervention by third parties, greatly reducing confidence in projected outcomes in any scenario of attack by nuclear missiles.

Don't get me wrong. I don't think a bunch of orbital missile interceptors, in and of themselves, will make us 'safe' or 'invincible'. I just think they'll make it such a hassle to try to calculate how to attack each other that nations will increasingly prefer just to negotiate.