By renaming the Defense Department the Department of War, President Donald Trump has restored the name that had been used until shortly after World War II.

The executive order on the name change, which Trump signed Friday, makes good on a pledge he had made for months. Trump has argued that “defense” was too politically correct a term, and that War Department “just sounded better.”

Here’s what to know about the name.

What’s the History of the Name?

George Washington established the Department of War in August 1789, months after the Constitution was ratified and he became the first president. The department oversaw the new nation’s military forces. Its first secretary was Henry Knox, who had served as a commander during the Revolutionary War and had, since 1785, been the war secretary under the Articles of Confederation, an early agreement among the colonial states.

The name was retained for more than 150 years, during which time the United States fought wars against Britain, Spain, Mexico and the Philippines, as well as the Civil War. It also fought wars against Native Americans.

The United States entered World War I in 1917 and, after the attack on the U.S. base at Pearl Harbor in 1941, joined World War II on the side of the Allied powers. When Trump floated the idea of the name change in August, he said it would be a reminder of U.S. military victories under the old name, citing world wars I and II.

Why Was the Name Changed to the Defense Department?

According to the Truman Library Institute, President Harry S. Truman changed the name as part of the National Security Act he signed in 1947, a time when the United States was the world’s only nuclear power and the Cold War was just starting.

The law merged the Navy and War departments and a newly independent Air Force into a single organization called the National Military Establishment, under a civilian secretary of defense who also oversaw the Joint Chiefs of Staff. Its first secretary was James Forrestal, who served for two years before resigning.

Two years later, Congress amended the National Security Act, and the National Military Establishment was renamed the Defense Department. Since then it has overseen wars in Korea, Vietnam, Afghanistan and Iraq.

Richard H. Kohn, a professor emeritus at the University of North Carolina at Chapel Hill who specializes in military history, said the name change in 1949 reflected the department’s expanded duties, which included war fighting, foreign policy, intelligence and, above all, national security.

In a nascent nuclear age, the new name also reflected an emphasis on avoiding war, Kohn said.

“The decision was definitely not about political correctness,” he said. “It was to communicate to America’s adversaries and the rest of the world that America was not about making war but defending the United States, and saying that if that requires war, there are four major armed services.”

Can Trump Do This?

Before the White House announcement, Jamal Greene, a professor at Columbia Law School, said it was not clear the president could make the change unilaterally. Acts of Congress established the Department of Defense and the title of secretary of defense, Greene said, so it was unclear if Trump’s name change would take effect immediately.

In his August remarks about the potential renaming, Trump said he had little doubt the new name would be adopted. “I’m sure Congress will go along if we need that,” he said, adding: “I don’t think we even need that.”

The president has more clear-cut power to order changes to geographical names as they are used in the United States. In January, he signed an executive order directing the federal government to rename the Gulf of Mexico to the Gulf of America, saying that the name had a “beautiful ring.”

Experts said the change in the gulf’s name put Democrats in an awkward position, since to contest it could be viewed as unpatriotic.

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This article originally appeared in The New York Times.

By Matthew Mpoke Bigg/Haiyun Jiang
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