Transgender service members don’t threaten the military’s combat readiness and they don’t cost U.S. taxpayers a lot of money, so there is no practical reason to kick them out of the military.

Sen. Susan Collins and three other senators have introduced legislation to stop President Donald Trump’s unnecessary and mean-spirited effort to prevent transgender Americans from serving in the military. The bill, also sponsored by Sen. John McCain, a Republican and chairman of the Senate Armed Services Committee, and Democratic Sens. Kirsten Gillibrand and Jack Reed, would make it clear that Congress expects the military to allow all who are qualified and can meet military standards to be allowed to serve. It also would prevent the Defense Department from removing or denying re-enlistment to currently serving military members solely based on their gender identity.

Collins and Gillibrand previously introduced an amendment to the military defense spending plan currently before Congress with the same provisions, but it became bogged down in negotiations last week.

“If individuals are willing to put on the uniform of our country, be deployed in war zones, and risk their lives for our freedoms, then we should be expressing our gratitude to them, not trying to exclude them from military service,” Collins said in a statement.

This is something everyone should be able to agree on. This isn’t a Democrat versus Republican or liberal versus conservative issue. It is a matter of common human decency and, if somehow that argument isn’t persuasive, smart use of taxpayer dollars.

Transgender service members make up a small portion of the U.S. military. Their health care, including transition care, accounts for a tiny fraction of the military’s budget. More important, their service has not disrupted readiness or unit cohesion, according to an analysis by the Rand Corporation done before the Obama administration lifted the transgender service ban last year. These fact didn’t stop Trump from erroneously citing these factors in his fallacious reasons for reinstating the ban.

In addition to the unnecessary human toll, kicking transgender service members out of the military will cost nearly $1 billion, which doesn’t even account for the time and money spent training these soldiers and sailors who are serving without any problems.

Because of the current uncertainty, many transgender military personnel are now caught in a “Don’t Ask, Don’t Tell” type of situation. That military policy, put in place by the Clinton administration, allowed gay people to serve in the military, but only if they didn’t disclose that they were gay. The policy was lifted in 2011. Collins was the leading Republican on legislation to end the policy.

Last year, the Obama administration lifted a ban on transgender military service, sending a message that these men and women were welcome in the military, prompting many to disclose that they are transgender. To now kick these people out of the military, as President Donald Trump said should happen (in a tweet), is cruel and unusual punishment.

That’s why it is so discouraging that Collins and McCain are the only Republican publicly involved in reversing the Trump transgender ban. Collins is the only Republican, along with 44 Democrats, to sign a July letter to Defense Secretary James Mattis urging him to advise the president to drop the policy change.

“Any American who wants to serve and meets the standards should be allowed to serve our country,” the senators wrote. “Transgender service members are serving with honor and distinction today and we ask that you, as secretary of defense, assure them that their service will not be ended simply because of who they are.”

This is a simple standard, backed by research and human decency, that all members of Congress should be able to support.