Obama and the Democrats have never liked missile defense. They think it is de-stabilizing because it frightens our enemies and makes them more belligerent. (Actually, missile defense frightened the Soviets, and made them less belligerent, but reality is not recognized by leftists.) Obama has wanted to cancel the deployment of the missile shield all along, so he has cooked up some reasons for doing so. The reasons stated do not stand up to scrutiny. Then one has to wonder about the tone-deaf timing of Obama's announcement of his decision. Why make the announcement on the anniversary of Russia's invasion of Poland 70 years ago? That is like poking the Poles in the eye. The Poles still have good reason to be afraid of the Russians, and the decision looks to them like the US has abandoned them to the Russians. The Obama Administration says the decision strengthens NATO. I don't think anyone can figure out how that is true. Then they say that Iran is not working on a long-range missile now, but rather is concentrating on Shahab 3, an intermediate range missile. They say that the THAAD system is not proven, and won't be ready for several years. Instead they are going to deploy the advanced SM-3. As it happens, the advanced SM-3 is a paper missile which also won't be ready for several years. The SM-3 is a ship launched missile that uses the Aegis Battle Management system. Thus the radar won't be as good as the THAAD system that would have been deployed in Poland and Czechoslovakia. From the reports I read it appears that the plan is to deploy the SM-3 from land bases. This is obviously something new that has not been proven. I suppose this is a win for Raytheon (the SM-3 supplier), Ted Kennedy, and Massachusetts. It may not be so good for Poland, Europe, or the USA. Here is a discussion of this, with comments by people knowledegable about missile defense who disagree with the decision.