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In his efforts to mask the seriousness of his actions around Russia and Ukraine, President Donald Trump has taken aim at one essential democratic institution after another—questioning the legitimacy of the press, the intelligence community, the courts, and, most recently, the House of Representatives itself. But he has so far mostly held his fire against both “his generals” and “our boys” in America’s military. “I will always stick up for our great fighters,” Trump promised his political supporters in Florida at a recent rally, championing on that day his recent decisions to pardon soldiers accused of war crimes.

The military, for its part, has had more mixed feelings. As a former chairman of the Joint Chiefs of Staff, General Martin Dempsey, described one such pardon, the president’s action was nothing less than an “abdication of moral responsibility.” Indeed, the military’s generally steadying reactions to the president’s worst moments of volatility have given members of Congress on both sides of the aisle reason to hope that the Pentagon at least will remain a check on presidential impulse that might really compromise national security, should other checking institutions fail.

But hoping that a president will defer to the judgment of the professional military is a sign that something has gone very wrong in America’s constitutional infrastructure. The American republic was, after all, founded on the complaint that the king had “affected to render the Military independent of and superior to the Civil power.” The Constitution’s Framers abhorred the British army, as much or more for its treatment of colonists in the years leading up to the war as during it. As Alexander Hamilton put it with characteristic clarity in “Federalist No. 26”: “The people of America may be said to have derived an hereditary impression of danger to liberty from standing armies in time of peace.”

While the risk of soldiers quartered in homes—one of the Framers’ chief complaints—is the least of our worries today, it was hardly the Framers’ only concern. They also feared the inspiring “man on horseback”—the charismatic military hero who could use his outsize popularity to thwart the initiatives of politically elected civilians. (Think of General Colin Powell’s highly effective campaign against President Bill Clinton’s efforts in the 1990s to lift the ban on gays in the military.) And they worried about the opposite problem, too—the danger posed by the potential rise of corrupt political leaders, who might seek to keep the military in line by insisting that it internalize the values not of professional ethics or the rule of law, but of the particular civilian leader in charge. As the political scientist Samuel Huntington famously explained in The Soldier and the State, such a mechanism could tie the military closely to one political party, and thereby make the military an enemy of democratic governance once that party left power.

In the end it was the experience of General George Washington that led the Framers to accept the necessity of a professional military. Washington’s struggles to manage bands of untrained rebel fighters made him a powerful advocate for the indispensability of training, regular structure, and rules of discipline for ensuring military effectiveness. The constitutional question was how, then, to capture the benefits of such a military while mitigating its many risks. The Constitution’s answer: Divide control over the military between the president and Congress. The president would command the armed forces; Congress would regulate them.

And regulate the military Congress has, with many of the Framers’ concerns in mind. To help insulate the military from partisan politics, for example, the law prohibits active-duty personnel from participating in partisan fundraising or rallies, from using their official authority or influence to advocate in an election, and from soliciting votes for any candidate. Elaborate rules of discipline and good conduct (including prohibitions against war crimes) are also codified in statutes passed by Congress; administered in key respects by military lawyers who report through their own, independent chain of command inside the Pentagon; and backed by federal law prohibiting any commanding officer from attempting to unduly influence the operation of this system of military justice. Historically, Congress even enacted legislation enabling a court-martial to reverse the president’s dismissal of an officer if the court determined the dismissal was “wrongful.” (This particular law, passed during the Civil War, was one neither President Lincoln nor his attorney general found objectionable.) In the years after September 11, professional military lawyers leveraged this legal framework against civilian political efforts to lift limits on torture and cruelty toward detainees.

In large part, these measures have worked. Congressional regulation has prevented the realization of the Framers’ worst fears—either a military that chronically runs roughshod over the preferences of elected civilian authorities, or a civilian leader able to exploit military might outside the rule of law for his own partisan ends.

This is part of what made President Trump’s recent pardons of Mathew Golsteyn, Edward Gallagher, and others like them, so troubling. Watching the president of the United States reward the violation of the most fundamental laws of war, inflaming America’s enemies and alienating America’s allies, was bad enough. But the president’s action appeared to be an intervention in otherwise semi-independent legal and disciplinary processes inside the military—an intervention for the purpose of currying favor with his political base. The pardons—driven by Fox News and reinforced by political rallies—added to the appearance, and reality, that the president regards the military as a tool of partisan politics, not as an institution whose unique constitutional position he has a duty to protect.

The good news, such as it is, is that the president’s word on these cases, and on much national-security policy more broadly, need not be the last. Congress still has all the constitutional power it needs to revisit whether existing regulations and disciplinary processes are adequate to deal with criminal behavior in the military going forward. Likewise, and well apart from impeachment, Congress can hold hearings to assess the national-security consequences of U.S. action or inaction on the ground, in Syria, Ukraine, or anywhere else. Hearings must take care not to ask military witnesses to choose sides in purely partisan squabbles. But it would compromise no constitutional value for Congress to seek the benefit of military expertise in reaching its own judgment about American national security, or otherwise to reassert its role in maintaining a dual system of civilian control. In the meantime, it would be a benefit to the country in more ways than one for Congress to remind the president that the military’s generals are not really “his.”

This story is part of the project “The Battle for the Constitution,” in partnership with the National Constitution Center.

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