Little has seemingly gone as Washington planned in the war against Iran.

The Iranian people have not risen up, one hard-line leader has been replaced by another, Iranian missiles and drones keep hitting targets across the Middle East, Iran closed the Strait of Hormuz, driving oil and gas prices up worldwide, and in sharp contrast to Trump’s demand for “unconditional surrender,” Tehran has rejected a 15-point U.S. plan for a ceasefire.

So how did things go so wrong?

As a scholar who researches U.S. forever wars, I believe the answer is simple: Trump, like other U.S. presidents before him, has fallen into what I call the trap of asymmetric resolve. In short, this occurs when a stronger power with less determination to fight starts a military conflict with a far weaker state that has near boundless determination to prevail. Victory for the strong becomes tough, even close to impossible.

When it comes to Iran, the Islamic Republic wants – and needs – victory more than the United States. Unlike the U.S., the Iranian government’s very existence is on the line. And that gives Tehran many more incentives – and in many cases very effective countermeasures – through which to fight on.

The trap of asymmetric resolve

Typically, in asymmetric wars the stronger side does not face the same potential for regime death as the weaker side. In short, it has less on the line. And this can lead to lesser resolve, making it hard to sustain the costs of war required to defeat the weaker, more determined rival.

Such dynamics have played out in conflicts dating back to at least the sixth century B.C., when a massive Persian army under Darius I was checked by a much smaller, determined Scythian military, leading in the end to a humiliating Persian retreat.

For the U.S. in the modern era, wars of asymmetric resolve have likewise not been kind.

In the Vietnam War, an estimated 1.1 million North........

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