Congress created the United States Department of Defense in 1949 as part of a comprehensive effort to modernize the military and adapt to the international order that was taking shape after World War II. Now President Donald Trump wants to change its name to the Department of War, its former name. That’s a mistake, [I believe].

National defense is and should be the primary mission of our military. Projecting strength, working with our allies, and countering our adversaries through diplomacy has helped keep us safe and prosperous. That’s a legacy that we should affirm, not abandon.

When the Defense Department was established, the Soviet Union was expanding its influence rapidly, leading to the creation of NATO; the Soviets were about to detonate a nuclear bomb. Mao Zedong was declaring the People’s Republic of China.

“It was a terrifying time for Americans,” David Sanger writes in the New York Times, “and the new name was intended to reflect an era in which deterrence was critical — because war, if it broke out among the superpowers, could be planet-ending.”

Deterrence, a key strategy for defense, was effective, and it remains critical. The Cold War ended, but Russia and China still threaten their neighbors. Instead of two nations with nuclear weapons, there are nine, and the weapons are more dangerous. Threats to the planet continue.

The Trump Administration has begun using the new [Department of War] name; but, ultimately, changing the Defense Department’s name is up to Congress. The legislative branch has shown an unfortunate tendency to defer to the president. This is a chance for it to assert its authority.

Trump likes the name War Department because it has “a stronger sound.” It evokes an era when the United States “won everything,” by which he means two world wars. He signed an executive order declaring that the department should be called the Department of War and its leader, Pete Hegseth, would be the secretary of war.

But the department’s history is not straightforward. Congress established the War Department in 1789. A few years later, it created a separate Navy Department. For much of American history, the Army and Navy were administered separately, causing rivalries. Creating the Defense Department with civilian leadership brought greater coordination.

Renaming the Defense Department can be seen as an exercise in branding — the idea that you can increase the value of a product or property by giving it a new name. It sends a message, like declaring the Gulf of Mexico is the Gulf of America and restoring the names of Confederate generals to military bases. It aligns with Trump’s America First philosophy and his disdain for soft power exercised through diplomacy and engagement. It suggests we’ve grown less committed to practicing defense.

It also plays in the hands of Russia and China, which portray America as an aggressive power that other nations shouldn’t trust. Trump’s executive order says the U.S. will “wage war to secure what is ours.” Some countries will take that as a threat.

The name War Department may have nostalgic appeal, hearkening back to an era before the frustrations of our military entanglements in Korea, Vietnam, Iraq, and Afghanistan. We are right to celebrate our military victories in World War I and World War II and to take pride in America’s crucial role in those conflicts. But we shouldn’t ignore that those wars were incredibly costly, causing tens of millions of deaths.

There’s an aphorism attributed to Sun Tzu, the legendary Chinese military strategist: The best battle, he wrote, is the one that you don’t have to fight. By that standard, the Defense Department has done its job well. Yes, America must be prepared to fight wars if necessary. But it’s much better to use our military strength and the power of our defense to prevent wars that aren’t necessary.        

Lee Hamilton, 94, is a senior advisor for the Indiana University (IU) Center on Representative Government, distinguished scholar at the IU Hamilton Lugar School of Global and International Studies, and professor of practice at the IU O’Neill School of Public and Environmental Affairs. Hamilton, a Democrat, was a member of the U.S. House of Representatives for 34 years (1965-1999), representing a district in south-central Indiana.a