Donald Trump took to Truth Social this week to declare an “Economic D-Day” against Iran. Threatening what he branded the “most crushing economic operation ever taken against any country,” the President warned that any nation providing a financial lifeline to Tehran would face ruinous secondary sanctions. The objective of these proposed sanctions is clear: force the Islamic Republic to yield its chokehold over the Strait of Hormuz and capitulate to American terms. The chances of its success are also clear: near-zero.

It is a familiar reflex of American foreign policy — the belief that enough financial pressure can break any regime’s will. But as an answer to the standoff in the Persian Gulf, it is a dangerous delusion. Washington is operating on a fundamental misunderstanding of its adversary. Iran will not relinquish control of the Strait of Hormuz because the country is virtually impervious to economic pain.

To grasp why maximum economic pressure fails in Tehran, both history and national character are important to understand. Iranians have lived under a web of international sanctions for most of the period since the 1979 Revolution. The country endured eight years of existential horror during the Iran-Iraq War — a conflict marked by horrific casualties, chemical weapons, and total economic isolation — without collapse.

Suffering is also deeply woven into the Iranian national psyche, both culturally and religiously. From the Shia tradition of martyrdom to a fiercely defensive nationalism, the regime and its people are conditioned to absorb deprivation as a condition of sovereignty. There is no evidence in modern history that financial pressure alone can force Tehran to surrender what it views as a vital national security asset.

Furthermore, the mechanics of modern economic isolation rarely match the rhetoric of Washington policymakers. Sanctions operate under the naive assumption that a nation can be cleanly sealed off from the global economy. In reality, Iran shares vast land borders across Asia and the Middle East that make absolute isolation impossible.

I was deployed as an Army Lieutenant Colonel during the 2010–2011 Afghanistan surge, and conducted operations along the border with Pakistan. I watched from the ridgelines as an endless, ungovernable stream of commerce and insurgents moved across treacherous mountain passes. Despite the full weight of the US military apparatus — and about 140,000 US and Nato troops — stopping that flow was a physical impossibility. The same dynamics apply to Iran’s rugged topography and sprawling trade networks into Central Asia, Iraq, and beyond.

We have seen this tactical hubris before. Decades ago in Southeast Asia, the United States deployed unprecedented airpower and interdiction strategies to sever the supply lines feeding North Vietnamese forces along the Ho Chi Minh Trail. America tried desperately to starve the Vietnamese war machine through physical and economic logistics, yet goods and materiel kept moving.

Economic blockades and maximum-pressure campaigns sound decisive in a social media blast or a White House press briefing. But coercive diplomacy fails when it confronts a regime whose survival and identity are explicitly built on enduring that very coercion. Trump’s “Economic D-Day” may cause severe hardship, but it will not clear the Strait of Hormuz. Tehran will simply do what it has always done: absorb the blow, adapt in the shadows, and wait Washington out.