When President Trump took to Twitter on the morning of July 26 to issue a series of lies about transgender individuals serving in the United States armed forces and announce a ban on open transgender service, he disrupted the lives and careers of thousands of transgender troops.

His announcement came as a shock to almost everyone, including members of Congress, military experts, and the Secretary of Defense.

While he claimed to have consulted with his “Generals and military experts,” that was not the case. Instead, he allied himself with Tony Perkins of the Family Research Council who dismissed the service of transgender individuals as the “social experimentation of the Obama era that has crippled our nation’s military.”

We hoped that the ill-advised ban would languish on the president’s Twitter feed, but unfortunately, he turned the tweets into a directive banning open transgender service on August 25.

The new directive bars enlistment by transgender individuals, prohibits coverage for certain critical medical procedures, and bans those currently in the military from serving, with the Secretary of Defense given discretion to determine how to carry out that ban.

Today, we and the ACLU of Maryland filed a lawsuit to challenge President Trump’s cruel policy on behalf of Petty Officer First Class Brock Stone, Staff Sergeant Kate Cole, Senior Airmen John Doe, Technical Sergeant Tommie Parker, Airman First Class Seven Ero George, and Petty Officer First Class Teagan Gilbert.

Our lawsuit argues that the ban violates the constitutional guarantees of equal protection and substantive due process by singling out transgender individuals for unequal and discriminatory treatment.

Every justification that the president has offered in support of the ban has already been thoroughly reviewed and debunked by the Department of Defense itself when it adopted a policy permitting military service by transgender individuals last year.

Military, medical and legal experts have concluded that allowing open service by transgender individuals, many of whom have been serving in silence for years, does not disrupt military readiness or unit cohesion and imposes negligible costs. By contrast, barring transgender individuals from joining the military and discharging those who are already serving is exceedingly costly and undermines national security and military readiness.

President Trump’s hateful and discriminatory agenda has nothing to do with military readiness. As Senator Tammy Duckworth of Illinois, a combat veteran, explains:

“When I was bleeding to death in my Black Hawk helicopter after I was shot down, I didn’t care if the American troops risking their lives to help save me were gay, straight, transgender, black, white or brown. All that mattered was they didn't leave me behind. If you are willing to risk your life for our country and you can do the job, you should be able to serve—no matter your gender identity or sexual orientation. Anything else is not just discriminatory, it is disruptive to our military and it is counterproductive to our national security.”

This policy is just another attempt by the Trump administration to target transgender individuals and push us out of public life. Our education, our careers, our health care, indeed our existence, is being jeopardized. Those who are serving our country and relying on the benefits that they have earned deserve a commander-in-chief who will fight for them, not against them.

As my brother, a reconnaissance platoon leader in the 82nd Airborne and executive officer in Army Special Operations Command (USASOC) who has deployed to Afghanistan wrote at the time of President Trump’s initial tweets:

“History has proven time and time again that restrictions against certain groups joining the military, such as African-Americans or Japanese-Americans, are self-defeating. The results of lifting these arbitrary restrictions have always been the same. The reasons given for the restrictions never came to fruition, were based on fear and prejudice, and the military was ultimately stronger based on a swell of new applicants and diversity in its ranks.”

President Trump can try to impose this transgender ban, but we will fight him every step of the way.