TORONTO – The key question about Iran’s energy-export terminal on Kharg Island is not whether the United States can seize or disable it. Of course it can. The real issue is what happens afterward, when the conditional logic that the US has applied to its alliances begins to shape allied behavior in turn. When allies’ behavior can no longer be assumed, American power becomes more constrained. The key variable is no longer what the US can do, but what costs others will be willing to bear. American primacy rested on a simple bargain—pay more, decide more, and allies follow. That bargain is broken.

© Project Syndicate