On September 2, after the most intense exchange of fire between the United States and Iran since July, President Donald Trump predicted that the renewed American campaign would not last long. In the same breath, he left open the possibility of further strikes. That contradiction now sits at the center of the war. Trump can order attacks, inflict damage, and threaten escalation. The harder task is ending the conflict without allowing the inevitable compromise to look like a retreat.

This was not the predicament Trump promised to inherit. He returned to office selling America First as an escape from costly “forever wars.” Yet six months after the United States and Israel began striking Iran on February 28, his administration is caught in a familiar strategic trap: Starting a war is often much easier than deciding what must happen before it can end.

The administration’s language betrays the strain. Trump has alternated between celebrating the damage inflicted on Iran, warning of new attacks, and insisting that diplomacy can still deliver a deal. In early August, he called negotiations Iran’s “last chance,” even as Tehran disputed that direct talks were taking place. Ambiguity can be useful in coercive bargaining. It becomes dangerous when the threat of force begins to substitute for a coherent political objective.

The cost of sustaining that posture is no longer theoretical. In July, Defense Secretary Pete Hegseth told lawmakers that the war had cost the United States an estimated $37.5 billion, including projected expenses through the end of the fiscal year. The administration was seeking still more money for Iran-related operations and to replenish expended weapons. Those costs do not, by themselves, prove that the war is unwise. They do, however, create pressure to demand an outcome grand enough to justify them.

This is where sunk costs become strategically dangerous. Leaders rarely admit that earlier sacrifices now require still more sacrifice. The process is subtler than that. Every deployment creates another asset to defend. Every escalation enlarges expectations of what victory must deliver. An agreement that might have appeared acceptable at the outset begins to look inadequate simply because more blood, money, and political capital have since been spent. Strategy bends around the need to prove that earlier decisions were worth their price.

The Strait of Hormuz turns this dilemma into geography. Military pressure has not erased Iran’s leverage over the waterway. In late August, Iranian officials said Tehran and Oman were still working on a shipping corridor, while Iran attached conditions to reopening the strait, including an end to the war, sanctions relief, and compensation. Washington need not accept those terms. But the bargaining itself is revealing: Overwhelming military superiority has not abolished geography, economic vulnerability, or Iran’s capacity to impose costs.

That is not an Iranian victory, nor must it be framed as an American defeat. States negotiate because war rarely gives either side everything it wants at a tolerable price. A workable settlement would protect the interests Washington genuinely considers vital while costing less than continued fighting. The political difficulty lies in distinguishing an imperfect outcome from an unacceptable one—a distinction that martial rhetoric tends to blur.

Congress has increasingly pressed that question. In July, the Republican-led House voted to limit Trump’s authority to continue military action against Iran without congressional approval, although the Senate blocked a similar measure. The votes divided largely along partisan lines, but the question beneath them did not: What political order is the United States trying to produce by prolonging the war?

If the objective is to prevent Iran from acquiring a nuclear weapon, then a military campaign paired with a negotiated nonproliferation agreement could, in principle, offer an end point. If the objective is to permanently dismantle Iran’s missile forces, transform its regional conduct, and strip it of leverage in Hormuz, the undertaking becomes vastly larger. Add regime change, and the definition of victory expands once more. These are not competing descriptions of one war. They are different wars, carrying different costs, risks, and timelines.

The danger is mission expansion by accumulation. A narrow objective fails to produce the expected concession, so Washington applies more pressure. When that fails, its demands grow. Eventually, the war continues partly because ending it has become politically more difficult than extending it. The original purpose remains in the speeches, but the conflict is increasingly sustained by consequences of its own creation.

That contradiction also runs through Trump’s political coalition. Some America First voices oppose the Iran war not because they reject military power, but because they believe force should serve limited, clearly defined national interests. Their challenge is difficult to dismiss: If the United States can destroy targets but cannot dictate Iran’s political behavior at an acceptable cost, what does another round of escalation actually buy? More leverage, perhaps—but leverage toward what?

“Peace through strength” can be a principle. It is not a strategy. Strategy requires priorities, limits, sequencing, and a plausible end state. Without them, strength becomes self-justifying. The more Washington escalates, the more it must demonstrate that escalation worked. The harsher the rhetoric grows, the harder it becomes to accept a compromise that would have looked prudent months earlier. What began as coercion then risks becoming compulsion—not for Iran, but for the United States.

Trump’s most credible exit may therefore require a narrower definition of success. An agreement governing Hormuz, restoring nuclear constraints, or establishing a broader de-escalation would not prove that American power had failed. It would demonstrate that military leverage has value only when it can be converted into a political result. Great powers do not establish their strength by fighting indefinitely. They do so by knowing which objectives matter, what force can realistically secure, and when bargaining has become the more effective instrument.

Trump has shown that the United States can impose enormous costs on Iran. His more consequential test is whether he can translate those costs into a stable settlement without repeatedly reaching for the threat of a wider war. If America First is to remain a doctrine of selective power rather than permanent coercion, that distinction will determine whether this war actually ends—or merely assumes another form.