Less than 24 hours after Secretary of the Navy Richard Spencer was fired, CBS News would tape an interview with the ousted official to discuss the case of disgraced Navy SEAL Edward Gallagher. Spencer was officially fired for directly communicating the White House without knowledge of the Secretary of Defense, which could be considered a breach of the chain-of-command and a fireable offense. His dismissal came after a prolonged effort by the president to nullify Gallagher’s court-martial process; this interference threatens the legitimacy of the entire military justice system. Most presidential tweetstorms and subsequent evening news parades can be ignored as another weekly scandal; this one cannot. The undermining of American military justice is woefully misguided and a threat to national security.

The Uniform Code of Military Justice (U.C.M.J.) was passed by Congress and signed into law by President Truman in 1950. These statutes govern the entire court-martial process which has jurisdiction over all military service-members. It covers conventional crimes — such as murder, burglary, and assault — as well as military infractions like desertion and insubordination. At its best, the court-martial system treats all personnel regardless of rank as equal before the law.

Military justice has been dismissed as either empty propaganda to cover up war crimes or an unnecessary burden that endangers troops. Detractors point to Islamic State videos of brutal beheadings to prove the enemy’s refusal of decency in warfare. Each of these critiques misses the point. Abiding by the law of war is a moral necessity and a national security imperative.

Secretary Spencer’s “acknowledgment of termination” letter explains the necessity of military justice. The most obvious benefit of a strictly enforced military code of conduct is “good order and discipline.” A commander’s ability to give and obey orders is what separates a professional military from a disorganized militia. Even the most well-equipped armed service is useless if the rank-and-file cannot execute directives. An effective enforcement mechanism is vital to maintaining adequate command and control necessary to achieve objectives and keep those in uniform safe.

Permanent boundaries for behavior also provide consistency and clarity throughout the organization. Rules of engagement — the guidelines for use of lethal force — may be updated by each new president. Ethical expectations must last longer than any single presidential administration, especially for long-serving military personnel. Military campaigns and tactical environments may change, but the standards for conduct must remain the same. As the Armed Forces become more diverse along with the country, a common set of rules is instrumental in ensuring individuals can work together. Without a predefined notion of justice, service members are left to second-guess themselves and their colleagues.

Military justice also provides soldiers, sailors, airmen, marines, and guardsmen with confidence in its mission and purpose. There are few things more threatening to national security than a fighting force without morale. Strategists throughout history have written volumes that have blamed military defeats on troop discontent. In business and in the military, a cohesive culture is hard to build but easy to destroy. This is why Eddie Gallagher’s own unit testified against him during his court-martial trial. The U.C.M.J. is not a bunch of words on paper meant to be used as a rhetorical cudgel against our adversaries. It is the ethos of the U.S. Armed Forces that allows active-duty personnel, veterans, and their families to sleep soundly at night.

Moreover, a lawless military is not a more effective force. It undermines American soft power and the ability to persuade. It invites aggression and lends legitimacy to our adversaries. The President thinks that military justice prevents troops from doing their job, but without it, their jobs become even more dangerous

It is likely true that our enemies will rarely follow any code of military justice. This does not change the necessity of military justice. It’s not about them, and it never was. It’s about us. There are countless philosophical debates to be had about whether warfare can be regulated. As long as humans fight wars, there will be crimes and injustices. Yet, we — as Americans and beneficiaries of the world’s most powerful military — can control how we fight and what we fight for. American national security benefits from military justice, and the American conscience requires it.