On: Can NATO survive Trump's changes of heart?

The question is not whether NATO can survive a change of heart. The question is whether an alliance built on the assumption of American constancy can survive being treated as a weathervane. The President of the United States has discovered that commitments are optional. This is not a new doctrine - it is the oldest doctrine of the strong: the belief that one’s own convenience outweighs the promises that made the strength possible.

I have seen this before. In the 1930s, we watched a great power withdraw into itself, convinced that the troubles of Europe were not its own. The result was a decade of catastrophe. The difference now is that the withdrawal is not a policy - it is a mood. And moods are worse than policies, because they cannot be reasoned with. They can only be endured, or outlasted.

The Atlantic Alliance was not built on affection. It was built on the recognition that our fates are bound together by geography, by history, by the simple fact that the same ocean does not protect us from the same dangers. To treat that recognition as a matter of personal whim is to mistake the nature of the structure. A foundation does not become optional because the builder has grown tired of the house.

What remains is not a question of survival. NATO will survive this, as it has survived other storms, because the alternative is worse. What remains is a question of cost. How much will we pay for the education of a man who does not wish to be taught? The answer, I suspect, will be measured in years of uncertainty, in the slow erosion of trust, in the quiet recalibration of every ally’s calculations. And when the bill comes due, the President who changed his heart will be long gone, leaving others to pay for the damage done to the idea that an alliance is more than a convenience.