As foreign policy luminaries rush to warn about the perils of a U.S. attack on Iran, there is widespread confidence in the White House that President Donald Trump can manage a strike’s fallout. This confidence reflects a years-long pattern that has shaped Trump’s thinking. Washington’s foreign policy establishment warns the president against some norm-breaking act. He ignores their advice and plows forward. And he faces no apparent repercussions. In 2018, when Trump broke with U.S. policy to move the American embassy in Israel to Jerusalem, I was serving in the State Department’s Bureau of Near Eastern Affairs. Our own bureaucratic experts predicted that the move would prompt widespread protests and violence against U.S. personnel, and we set up task forces and evacuation plans for a doomsday that never came. This dynamic repeated itself last June, when Trump joined Israel’s strikes on Iran’s nuclear program. Analysts warned that the decision would trigger a broader war and hasten Iran’s nuclear breakout. Once again, little happened. When the administration ousted Venezuelan President Nicolás Maduro in January, pundits insisted that his country and even the region would plunge into chaos, but nothing of the sort has yet occurred.

It is easy to see why Trump would believe that the warnings about another attack on Iran are overwrought and that he can repeat his formula of decisive action and a clean exit. But this time is different. I spent 18 years working on Iran in various U.S. government capacities, including as President Joe Biden’s Iran director and on Trump’s negotiating team in the spring and summer of 2025. From that experience, I can see that Trump fundamentally fails to grasp that Iranian weakness will not lead the country to capitulate at the negotiating table. On the contrary, Iran’s present fragility only narrows the space for meaningful compromises. Nor does Trump understand that Iran faces entirely different conditions than it did in June 2025, when it chose to de-escalate. The Islamic Republic now believes that Israel and the United States intend to repeatedly strike its ballistic missile program—the foundation of Iranian self-defense—and that it must be more aggressive to forestall the kind of perpetual assault that could topple it altogether.

Trump’s own behavior also increases the risk of escalation. The president’s ever-intensifying wish to be seen as a historic peacemaker has led him to an unnecessarily binary choice—strong-arm Tehran into a major new deal or use substantial force. And the nebulousness of his motives makes this flash point much more dangerous. Trump seems interested, in no particular order, in demonstrating the prowess of the U.S. military, strengthening his negotiating position, showing he was serious when he vowed in a January Truth Social post to protect Iranian protesters, and differentiating his approach from President Barack Obama’s. This mishmash of objectives contrasts with the focus he brought to his previous successful operations and will make him less prepared if a strike does not yield the expected, swift capitulation. All told, today’s conditions mean that an attack by the United States on Iran could result in unexpectedly deadly retaliation—and a much longer and potentially damaging conflict for Washington.

Strategically........

© Foreign Affairs