“Discipline is the soul of an army.”

When George Washington wrote those seminal words in his Instruction to Company Captains, our first American president captured the essence of what forms the foundation of a great military: good order and discipline.

As a former commander, I learned that good order and discipline isn’t a mere slogan. Rather, it’s the North Star that ensures we always fight with honor. It’s how our military became the greatest fighting force the world has ever seen, while adhering to the laws of war and rejecting wanton, reckless violence.

Good order and discipline is truly the soul of the United States military, and that soul is now threatened by a commander in chief who glorifies torture, betrays American allies and celebrates war criminals and despots. A man who day by day, tweet after tweet, betrays long-held military values with reckless comments and undisciplined actions.

As someone who cherishes the military precisely because of its values, I’ve been disheartened to watch general and flag officers who demonstrated bravery and valor on the battlefield abroad, refuse to act at home. Crossing their arms, staring down at the table, our military leadership appears unwilling or incapable of dealing with President Donald Trump.

Yet looking away will not change the reality that the commander in chief threatens to transform the U.S. armed forces into a brutal and violent fighting force that is unaccountable to the chain of command, not bound by the laws of war but rather devoted to supporting one man.

The secretary of the Navy used one of his last official acts to inform the commander in chief that, “I cannot in good conscience obey an order that I believe violates the sacred oath I took in the presence of my family, my flag and my faith to support and defend the Constitution of the United States.”

The forced resignation of the secretary of the Navy followed the president’s deeply troubling interference in the Navy’s attempt to review whether Chief Petty Officer Edward Gallagher should retain his Trident after being acquitted of murder charges, but convicted of conduct that violated what the U.S. Department of Defense Law of War Manual describes as “one of the oldest rules in the law of war”: the respectful treatment of enemy dead.

The decision to review Gallagher’s fitness to remain a SEAL was a reasonable course of action to preserve good order and discipline. It was not unusual. Since 2011, the Naval Special Warfare Command has taken away Tridents or special warfare combatant-craft pins from 154 operators.

By disrupting the Navy’s review, Trump demonstrated contempt for the judgment, authority and leadership of the Navy. This could not have come at a worse time. The commander of the Naval Special Warfare Command, Rear Adm. Collin Green, has been prioritizing the restoration of good order and discipline. With one tweet, Trump torpedoed the effort.

No one should wonder why Trump felt emboldened to take such action. Generals, admirals, successful business executives — all have proven incapable of withstanding the erratic demands of a petulant commander in chief.

Retired military leaders have begun sounding the alarm. Yet those in real positions of power are nowhere to be found.

The silence of civilian and uniformed military leaders speaks volumes, and the public can be forgiven for mistaking that silence for tacit agreement with Trump’s offensive attempt to normalize war crimes and his degrading characterization of our service members that was captured in a single tweet: “We train our boys to be killing machines, then prosecute them when they kill.”

How can Americans understand military values if the men and women entrusted to defend them fail to act when those values come under attack?

I’m not asking the impossible. In 1949, when the Truman administration moved to cancel construction of the USS United States, the secretary of the Navy and several top admirals were so alarmed by a decision they believed compromised national security that they resigned en masse in protest. During the Korean War, the United States struggled to blockade the Korean Peninsula, validating the concerns of Navy leadership. Because leadership spoke up, Congress had the necessary information to positively rebalance the military’s force structure in the following decade.

They did their duty. Now is the time for our civilian and military leaders to do theirs. To refuse to obey orders that are unconstitutional or unlawful. To strongly advise against improper orders that destroy good order and discipline. And if that advice is ignored, to honorably resign and inform the American people and their elected representatives why such action was required.

Past officials have taken such principled action when forced to confront a corrupt president. I implore those now in power to uphold the oath they swore to support and defend the Constitution of the United States against all enemies, foreign and domestic, before it is too late.

Tammy Duckworth, a Democrat, represents Illinois in the U.S. Senate.

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