Seems like they're having trouble recruiting people to serve as America launches headlong into GWOT 2.0 with no plan. It makes sense that people aren't signing up: it's a very unpopular war that was started by assassinating leaders during peace talks and bombing an elementary school, and it's not one they're winning.
And it's also a war with no clear benefit to Americans, which Marco Rubio admitted they were dragged into by Israel.