Trump revives rare wartime rhetoric: The history of ‘unconditional surrender’ and what it means now

When President Donald Trump issued a dramatic message to Iran this week: “UNCONDITIONAL SURRENDER!” it wasn’t just a policy threat. It was a phrase deeply rooted in American military history, one that has only been invoked during the most extreme wartime confrontations: the Civil War and World War II.

The United States has demanded “unconditional surrender” only a handful of times, and when it has, it meant complete capitulation; no negotiations, no guarantees for the losing side. Trump’s use of the phrase now, in the midst of escalating conflict between Iran and Israel, raises the stakes far beyond the usual bounds of diplomacy.

Where the Phrase Comes From

The first prominent American use of “unconditional surrender” came during the Civil War. In 1862, Union General Ulysses S. Grant demanded the unconditional and immediate surrender of Confederate forces at Fort Donelson, Tennessee. The phrase became so closely associated with him that he earned the nickname “Unconditional Surrender” Grant. However, even later in that war, terms of surrender, such as those offered to Robert E. Lee at Appomattox, were far more lenient and aimed at reconciliation.

But the term entered global politics in a more lasting way during World War II. At the Casablanca Conference in January 1943, President Franklin D. Roosevelt and British Prime Minister Winston Churchill announced that the Allied powers would accept nothing less than the unconditional surrender of Nazi Germany and Imperial Japan. The message was simple: the Axis powers would not be allowed to bargain their way out of defeat.

That commitment was reaffirmed in the 1945 Potsdam Declaration, which demanded that Japan surrender unconditionally or face “prompt and utter destruction.” Japan initially rejected the demand, prompting the U.S. to drop atomic bombs on Hiroshima and Nagasaki. Days later, Japan did surrender, fully and without conditions. Germany had already done so in May 1945, bringing an end to the European theater.

What About Modern Conflicts?

In the decades since World War II, the United States has fought numerous wars, but it has almost never used the phrase “unconditional surrender.”

In Korea, Vietnam, and both Iraq wars, U.S. policy objectives were more limited. The Korean War ended in a ceasefire. Vietnam ended in withdrawal. In 1991, after pushing Iraqi forces out of Kuwait, the U.S. allowed Saddam Hussein to remain in power under ceasefire terms. Even in the 2003 Iraq War, which resulted in the fall of Saddam, the U.S. did not formally demand or receive an unconditional surrender. Instead, Saddam was given an ultimatum to leave the country, and the invasion proceeded when he refused.

The language of modern warfare has emphasized diplomacy, strategic deterrence, and negotiated transitions; not total, no-conditions defeat.

President Trump’s revival of the phrase

That’s what makes Trump’s use of “unconditional surrender” in 2025 so significant and so rare. The message came shortly after a Situation Room meeting with national security advisers, as the U.S. weighed options in response to Iran’s confrontation with Israel. While the administration has remained vague on next steps, Trump’s public language was blunt: Iran must surrender completely, or face the consequences.

President Trump’s use of the phrase may be designed to project strength. But its historical weight cannot be ignored.