In my mind the foremost need to save our planet is to give those nations, with sufficient destructive power to end it, the desire to survive. Russia is the most likely candidate right now, and it`s doing so poorly that I would not be surprised if they decided to take the rest of the world down with them.
That situation, the one we have in Russia today, is really our responsibility. The previous two threats to our planet, Germany and Japan, have been neutralized by making them prosperous. They have too much to lose to embark on a destructive rampage again. But we missed the boat with Russia.
Essentially we have been trying to diminuish Russia, just the opposite of what we did with Japan and Germany, or Italy for that matter, but they really did it on their own.
So if helping to make, or at least allowing Russia to sink into an economic abyss, was not enough, we now threaten them with a missile defense system that would eradicate the cornerstone of all the mutual defense treaties we have with Russia. Having worked entirely on the Star Wars defense system for my scientific career, I know that it cannot work, except perhaps for the ship based system advocated by responsible scientists, and even Russia.
But we persist in developing a land based system that is secure but cannot solve the decoy problem. A space based system would work as shooting down boosters is quite easy and there is no discrimination problem. But space based systems are inherently vulnerable. There is no way to protect anything in space, unless it is so far away that it has no defense value.
Sorry to go on about Star Wars, but the point is that the future of the Earth lies in the hands of the United States. The big corporations like Raytheon want the profits associated with missile defense deployment. (By the way I was a Raytheon Fellow at Harvard). Wanting profits is not bad in itself, but normally the government intervenes when it gets out of hand, like monopolistic practices. But now we have Clinton endorsing missile defense, perhaps to take a campaign issue away from the Republicans, or maybe to cover his personal mishaps. We have lost the check and balance on this issue.
In 1987, when we last faced the threat of missile defense deployment, only the Republicans, who represented aerospace corporate interests, were in favor of deployment. The democrats sided with the scientists. But now the scientists are alone in condemning deployment, at least in the US.
So not helping Russia was a mistake. But we are now in the process of threatening Russia, and they are easily threatened. Also crazy enough at the top to do something irrational- especially since the KBG is taking over the country.
My guess is that a crisis will emerge in which they will threaten to launch if we deploy. Then it`s just a push of the button away from it actually happening. Hopefully the US will not let relations deteriorate to that point. But nobody in either party seems to be concerned about the seriousness of our present situation. They all think the Cold War is over, and Russia no longer matters.