India, July 19 -- Trump seems to believe that a constant stream of bluster and bravado gives him leverage, but in practice, it does the opposite. It signals uncertainty, and adversaries notice.

Not long ago, President Trump stood before the cameras and declared victory. The memorandum of understanding he'd just signed with Iran, he claimed, "achieves everything we set out to accomplish."

The Gulf war would end. Oil tankers would glide safely through the Strait of Hormuz again. Peace, he implied, was simply a matter of putting his name on a piece of paper. Less than a month later, that memorandum is worth about as much as the paper it's printed on.

Fighting has resumed. Missiles are flying again. And the Strait that Trump promised to re...