Sen. Lindsey Graham answers questions about the Russia investigation on Capitol Hill on May 23. (Melina Mara/The Washington Post)
M.L. Cavanaugh is an Army officer and a non-resident fellow with the Modern War Institute at West Point.

Congress is in recess, and members have returned to their districts to hold town hall meetings, fundraisers and, in a few cases, don military uniforms to serve in the National Guard or Reserve.

They shouldn’t.

As an Army officer I appreciate and admire their desire to serve. We need more citizens who want to serve in politics or in uniform. But allowing representatives of the legislative branch of government to act as officers in the coequal executive branch impedes their ability to make independent strategic judgments about war, violates the spirit of Defense Department guidelines and flouts the nonpartisan traditions of the military profession.

Though Department of Defense Directive 1344.10 doesn’t ban Guard and Reserve officers from serving as elected officials, it discourages, and in some cases prohibits, active duty military personnel from engaging in a litany of partisan political activity, including, but not limited to, partisan fundraising, partisan public discussion and writing partisan “political articles, letters, or endorsements.”

[The Marines’ naked-photo scandal shows military culture is still sexist]

But as any military man or woman will tell you, it’s a false distinction: Commissioned officers are all held to the same standards of personal conduct and fidelity to their oath, whether serving on full-time active duty — as I do — or as part-time Guard and Reserve officers. The military profession strives for thorough nonpartisanship to prevent politics from dividing troops and alienating the military from any segment of the American public.

(Lest I run afoul of my own obligations, I’ll state here that the views I’m expressing are mine alone and do not reflect the official policy or position of the Army, the Department of Defense or the United States government, and that I followed established protocol before this article was published.)

The point is that our members of Congress who serve in the Guard and Reserve, while technically not breaching the rules, are violating their spirit — that military officers should remain nonpartisan and serve with fidelity to the Constitution, not to an ideology, program or point of view. That’s nearly impossible, though, for military-serving members of Congress when you consider that they’re all members of either the Democratic or Republican parties. They have built-in allegiances to party agendas that can easily run counter to their sworn duties as military officers, particularly when carrying out their legislative duties related to the funding of our armed forces and the conduct of war.

Consider a recent op-ed written by Rep. Adam Kinzinger (R-Ill.), which included the bio line: “Adam Kinzinger is a Republican representative from Illinois and a major in the Air National Guard.” He’s identified as both a partisan and an officer, and in the article, he chides members of his own party over the charged issue of health-care reform. Not only does he muddy the waters by presenting his military role as a credential — without an appropriate disclaimer, and in relation to an article that has nothing to do with the military — he questions the tactics of congressional colleagues with whom he may one day vote to send service members (potentially himself included) into harm’s way to fight.

There’s Rep. Tulsi Gabbard (D-Hawaii), a major in the Army National Guard. Earlier this year, she traveled to Syria and met with its president, Bashar al-Assad, about that country’s ongoing civil war. While it’s not uncommon for members of Congress to take fact-finding trips to the Middle East, it’s highly unusual for one to meet face-to-face with a dictator actively contesting American interests in a war zone where our military personnel currently operate, and to which she could be deployed.

Rep. Duncan D. Hunter (R-Calif.) is a major in the Marine Corps Reserve and sits on the House Armed Services Committee — which directly oversees and drafts policy related to the military he serves in. The list goes on.

To be sure, going all the way back to George Washington, Americans have elevated veterans to high office. But there’s a difference between election to Congress after military service and doing both simultaneously. Military officers in the legislative branch aren’t functioning as a fully independent check on the executive branch if they’re serving in it.

And let’s face it, no one is going to treat members of Congress like others in uniformed service: The mere presence of such politically important individuals in a military unit almost certainly undermines the immediate chain of command. Plus, Guard and Reserve training requires 39 days per year, a condition any busy politician, even with best intentions, would find difficult to meet. As The Post reported in 2015, Sen. Lindsey Graham (R-S.C.), an Air Force JAG officer, rose through the ranks to full-bird colonel, even though, over a 10-year period, in eight of those years, he failed to complete “the minimum number of hours.” If it comes down to a shooting war, what are the odds that any congressman or congresswoman in the Guard or Reserve will wind up fighting in a foxhole? In 2003, the Army Reserve denied Rep. Steve Buyer’s (R-Ind.) request for a combat assignment in Iraq. Kinzinger, Gabbard and Hunter were forward-deployed while on active duty, but that was before their time in Congress.

One cannot, as Kinzinger’s website says, balance military “service with his duties in Congress.” War demands military officers execute the will of the commander in chief and follow command orders, while members of Congress are required to represent the will of the people and provide loyal criticism on matters of defense. These blurred lines might slide by today, and some may be able to distinguish one role from another at peace — but at war, one’s service can either be as a military officer or an elected representative, not both. When there’s a real fight, our country has chosen to separate political power from the military profession.

[I took an Afghan war vet to Brad Pitt’s bad, anti-military movie]

Pulling double-duty this way may not be proscribed by statute, but its constitutionality can be challenged in light of Article I, Section 6’s directive (known as the Incompatibility Clause) that “no Person holding any Office under the United States, shall be a Member of either House during his Continuance in Office.” A principle that, in 2006, the military’s highest court invoked when reversing a military court’s conviction because Graham served as one of the appellate judges in the case.

Military service is a privilege, one that comes with sacrifice. That’s why, as I explained in an essay several months ago, I don’t vote — to guard against injecting myself into the partisan fray in any sense. I don’t expect everyone to apply that standard when it comes to voting, but I believe that no matter who you are, simultaneously being an officer and serving in Congress are not compatible. Ordering a halt to this dual service would strengthen our nation’s defense and uphold our tradition of separating the powers. For a country that cherishes its institutions, it’s the right thing to do.