Over 50 House Democrats have sent a letter to Secretary of Defense James Mattis and Joint Chiefs of Staff Chairman General Joseph F. Dunford, Jr. to urge them to defy Donald Trump’s arbitrary decision to ban transgender people from the military.

Transgender people have been serving openly for over a year with the overwhelming support of their fellow troops and commanders, but Trump’s tweets announcing his decision have thrown the military into upheaval. None of the top brass from any branch of the military has announced support for Trump’s decision. In fact, most have expressed their disapproval.

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While Trump claimed in his tweets to have consulted with military leadership, even the Secretary of Defense found out about Trump’s decision in his three tweet missive.

“Unfortunately, President Trump’s proposed ban is yet another troubling sign of his willingness to make impulsive policy decisions while ignoring military leadership,” Congressman Jerrold Nadler, senior Member of the House Judiciary Committee, said in an emailed statement. “We appreciated the measured response of Secretary Mattis General Dunford and other military leaders in response to President Trump’s rash announcement of a proposed discriminatory and unjustified ban on military service by transgender individuals. We would urge President Trump to stop making policy via Twitter and to consult America’s professional military leadership before making decisions that affect the lives and safety of our citizens.”

Trump’s claim that providing gender reassignment surgery to transitioning service members has also been thoroughly debunked. The military spends 10 times more to provide Viagra to military members than it would pay for all surgeries for transgender people.

Related: Former Navy surgeon: I’ll perform free surgeries for trans military personnel

The letter says the Congress members want to “remind you not to comply with any unconstitutional directive which may ultimately be issued” and that “the Supreme Court has also previously observed that the government is subject to constitutional limits even ‘in the area of military affairs’.”

A copy of the entire letter is on the next page. Whether or not the military will ignore it remains to be seen.