Since President Trump announced in March that the Pentagon would prohibit many transgender people from serving in the military, thousands of Americans have been in limbo, not knowing whether their careers were over or whether they would be barred from even joining the armed forces.

Federal courts have put a temporary hold on this directive, which bans “transgender persons who require or have undergone gender transition” unless the Pentagon grants them an exception. In the meantime, a growing body of research and expert opinion supports the only fair and just solution: Repudiating Mr. Trump’s cruel decision and giving transgender people the same right to serve their country in a military uniform as any other citizens.

In separate statements over the past month, the chiefs of the Army, Navy and Air Force; the commandant of the Marine Corps; and the incoming commandant of the Coast Guard, testified to Congress that transgender service members do not impair the cohesion of military units or discipline.