Ok... I don't buy it. If I'm understanding the theory correctly, I don't buy it.
Simply because we post a completely defensive system for our allies benefit, doesn't look to me like a cause for unintended consequences.
The implication is that if we don't choose to advance our military, that no one else will either, and everyone will live in peace and happiness for all eternity. If that were true, then we never would have advanced beyond metal swords and iron armor.
The fact is, other nations of the world are advancing, whether we choose to or not. As America becomes (relatively) weaker, our enemies will be more and more likely to become a threat not only to us, but our allies.
You don't see Russia discontinuing to develop new and more deadly weapons. Why is it you are not sending messages to them saying they should stop before America becomes belligerent? Did they not invade one of our allies? Did we invade one of theirs? Why don't you tell them to stop making these super deadly weapons, used offensively to kill masses of people, unlike our defense shield, only used to save masses of people?
Russia Tests Giant Fuel-Air Bomb
"I think the likelihood is that this is the world's biggest non-nuclear bomb,"
You know... I think I'm feeling a bit belligerent. Are you feeling a tad belligerent?

Yes I can feel it now! We're getting very belligerent! Nobama, you feel it? Rob you feel it? United, you feel us all getting belligerent?
Your are right Scot! We're all getting belligerent from Russia's bomb testing and weapons race! We're all getting belligerent!