WASHINGTON DC:  Since its founding almost 250 years ago, the United States has been uniquely fortunate that its military has never once become a threat to its democracy. But that could now change because President Donald Trump is trying to use the military – and the men and women who serve in it – as a cudgel against his political adversaries, whom he describes as “the enemy from within.”

The American military hasn’t been pushed into partisan politics like this since at least the constitutional crisis of 1867, when President Andrew Johnson and the Republican-controlled Congress battled over Reconstruction. By inserting US troops into American cities, Trump has introduced a clear and present danger to American democracy.

The country’s founders worried deeply about such threats. The Declaration of Independence includes among its central complaints against King George III that “He has affected to render the Military independent of and superior to the Civil power.”

The founders also worried about their fellow citizens in uniform. During the British siege of Boston in 1775, the Provincial Congress of the Massachusetts Bay Colony declared: “we tremble at having an Army (although consisting of our countrymen) established here, without a civil power to provide for and control them.”

Thirteen of the 85 Federalist Papers – the essays that Alexander Hamilton, James Madison, and John Jay published to build support for ratifying the Constitution – deal directly with concerns about establishing a federal army. In the end, ratification of the Constitution was made possible only by adding an amendment assuring that “the right of the people to keep and bear Arms, shall not be infringed.”

When George Washington called up (and then personally commanded) the militia that suppressed the 1794 Whiskey Rebellion in western Pennsylvania, Congress required a Supreme Court justice to validate his judgment that an insurrection was occurring. Then, in 1807, Congress enacted a series of laws known collectively as the Insurrection Act, which limit the president’s ability to use the military domestically. A president can call out military forces only if a governor has requested it; if there is a violent insurrection, invasion, or armed rebellion; or if states are denying Americans their constitutional rights.

Domestic use of the US military was further constrained by the 1878 Posse Comitatus Act, which prohibits military involvement in domestic law enforcement unless authorized by Congress.

The Insurrection Act is often referred to as an exception to the Posse Comitatus Act, but in fact both are constraining legislation: they permit domestic use of military force only under narrow, specified circumstances.

Yet Trump is already using the US military for law enforcement – deploying troops in support of federal immigration officials – and he clearly has no intention of stopping.

He has done so over the objections of state governors in California, Oregon, and Illinois, and he has neither invoked the Insurrection Act nor claimed that Americans’ constitutional rights are being infringed by the states where he has sent (or is attempting to send) troops. That means he is in violation of both the Insurrection Act and the Posse Comitatus Act.

What is so curious about America’s current predicament is that Trump has a legal path for the actions he has taken: he could invoke the Insurrection Act, which grants the president wide authority to determine that a rebellion, invasion, or insurrection is occurring. Because he has not done so, he is drawing objections from federal courts for circumventing both the law and gubernatorial authority.

But America’s highest courts have historically provided wide latitude to presidents on military issues. If the Supreme Court were to take as expansive a view of presidential authority to deploy the military as it did in its immunity decision last year, we could see a dramatic expansion of executive power that negates the limitations established in the Insurrection Act and Posse Comitatus.

How can America get through this unprecedented challenge? One factor is the US military’s professionalism, as evidenced by the behavior of senior officers who were recently summoned to Virginia from around the world to hear from Trump and Secretary of War Pete Hegseth. America’s generals had a duty to be present, but they also bore a duty not to participate in the political circus that Trump and Hegseth created that day. They acquitted themselves admirably.

But the military cannot save Americans from the political leaders they elect. In the American system, solutions to political problems must be civilian in nature. Most importantly, Congress ought to exercise its Article I responsibilities and prevent Trump’s overreach of executive power. It can, and should, insist that it alone holds the power of the purse.

Recent developments also make clear that Congress should amend the Insurrection Act to limit a president’s authority to declare that an insurrection is occurring, and to require that such determinations be validated by authorities outside the executive branch. For now, governors should sue the federal government for infringing on their sovereign powers. The Office of the Special Counsel should enforce Hatch Act restrictions against using the federal government for partisan purposes. And “We the People” should scold our elected representatives for jeopardizing 250 years of success in keeping the military and politics separate.

[Kori Schake, the Director of Foreign and Defense Policy at the American Enterprise Institute, was director for Defense Strategy and Requirements on the National Security Council under President George W. Bush. She is the author of The State and the Soldier: A History of Civil-Military Relations in the United States (Polity Books, 2025)]

Copyright: Project Syndicate, 2025.

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