If they need large numbers of soldiers, fire all our current generals and admirals, no women in anything besides admin and hospital medical, no women officers, end the woke and homo crap (no more red high heel marches).
Allow lewd nose art again, and leave them alone on liberty call in foreign ports. Stop with the pointless idiotic foreign adventures. Run the USAF like SAC and TAC. Fun the fleet like Halsey and Nimitz and King. Run the Army like it was in the Fulda Gap days. Let em have fun in Germany with the women and beer.
In short, make it macho and tough and fun again. You’ll have all the volunteers you need.
Requiring women to register is a conversation to be had. Might even illustrate what a bad idea this is for military readiness and national security.