Jackson Fleming was arrested on suspicion of sending an online threat through a social media application concerning the academy, federal prosecutors said.
Retired Adm. Robert P. Burke — once the second-highest uniformed officer in the Navy — declined to address the court before a judge sentenced him Tuesday.
Under the new guidelines, troops granted a medical waiver must receive treatment and see the medical condition resolved within a year or face separation.
The strike comes two weeks after another military strike on what the Trump administration says was a drug-carrying speedboat from Venezuela that killed 11.