I am the grandson of a World War II veteran survived by a politically divided family and the husband of a gay, active duty military member. For me, the imperative to honor the courage and sacrifices of those who serve — regardless of political persuasion or personal identity — has always been crystal clear, and absolute. As a nation, we have long held an unspoken covenant: when one among us signs that line and dons that uniform, committing to put their life on the line to serve and defend all of us, we have their back. No exceptions.

So you can imagine my disgust when a Washington politician — a rich kid with bone spurs who never spent a day in uniform — signed an executive order denigrating the service of military personnel who happen to be transgender. But Trump’s ban on transgender servicemembers isn’t just a violation of social values or crude politicization of the military for partisan gain. It is a dangerous directive that will sow distrust and division. It will weaken the readiness and cohesion of our military. It will make our nation less secure.

A core commitment of our military has always been standing by its people. Whether it’s a wounded soldier on a battlefield or a veteran suffering PTSD from a long-forgotten war, no soldier gets left behind. This commitment — both organizational and individual — binds service members to each other and to their mission. It is the solidarity at the heart of our military’s strength.

Throughout our history, this commitment has inspired patriotic Americans from all walks of life to set aside their differences and find camaraderie in uniform. Liberals and conservatives, Republicans and Democrats, whites and minorities, U.S.-born citizens and naturalized immigrants, gays and straights, men and women — and yes, trans men and trans women. Even as I type these words, American soldiers from each of these groups are deployed to combat zones. Americans from each of these groups have also made the ultimate sacrifice for our nation. Trump’s disgraceful order not only singles out and dishonors one group of service members, it also commands the military to violate its fundamental oath to leave no soldier behind.

Trump justified his ban in his Jan. 27 executive order by attacking transgender soldiers’ “commitment to an honorable, truthful, and disciplined lifestyle”. Titled “Prioritizing Military Excellence and Readiness,” Trump used language that disparaged the patriotism of service members and claimed their personal identity precludes the “humility and selflessness required of a service member.” And because the order was purposefully cruel, he added that transgender individuals cannot exemplify these values even in their personal lives, an area the government — let alone a convicted felon — has no business commenting on.

But these attacks are not grounded in truth or evidence. Military experience, service history, and available evidence all indicate that transgender men and women are capable, competent service members that do not detract from unit readiness or effectiveness. This is why active-duty troops across all branches and ranks support their transgender colleagues. Like all dedicated service members, transgender soldiers have undergone rigorous training, built expertise critical to military operations, and proven their ability to serve with excellence and honor.

Humiliating and expelling these dedicated professionals — many of whom have served for years and are essential to their teams — will not enhance readiness or effectiveness. It will not promote the so-called “meritocracy” unironically touted by Trump’s woefully underqualified Secretary of Defense. It will not make our military more lethal or our country safer. This order serves only two purposes: to score partisan political points in a manufactured culture war and to purge the military of those who don’t conform to MAGA ideology. But these will come at the cost of our military’s integrity, unity, and operational effectiveness.

To be clear, Trump’s order, however it is translated into operational policy, will not prevent all transgender individuals from serving in the military. Transgender individuals have always served in our military and will continue to do so. But the order will force those who do to hide their identities, to maintain a wall of secrecy between themselves and their fellow soldiers.

We have lived through the years of Don’t Ask Don’t Tell, when thousands of gay, lesbian, and bisexual servicemembers were discharged on account of their sexual orientation — and countless more lived in fear of being outed. That policy did not strengthen our military readiness or bolster morale. My husband, who was a cadet at the U.S. Air Force Academy when it was repealed, can attest to the value of being able to bring his whole self to his service. No soldier should live under the threat of being dishonored or discharged because of who they love or how they express their gender identity.

The U.S. military is not a homogenous group of yes-men, and it shouldn’t be. It is composed of millions of diverse individuals who disagree on many things but unite around their common commitment to patriotic service. In return, the military and our nation have always pledged to have their backs, and to leave no soldier behind.

As our troops watch their fellow soldiers be targeted and dismissed, as commanders are faced with gut-wrenching dilemmas to betray their subordinates or face career-ending consequences, as political ideology becomes a loyalty test for rank advancement, this executive order will crush morale and fracture the unity at the core of our military’s strength. It is a stain on our national honor and will make us less safe in an increasingly dangerous world.

Johnny Weixler is a proud military spouse, father, and mental health nurse practitioner, who lives in Colorado Springs.