So what do you think happened to the military forces of the nations of earth ?

So we know after first contact 2063, humans rebuilt by 2110 earth has been rebuilt with a united earth. starfleet was founded in 2130 and there is the military assault command.

I'm wondering what do you think happened to the military forces of the earth nations after ww3 but before the 22nd century.

Like the Chinese armed forces, the USA armed forces, Russian armed forces etc.

In enterprise where they tried to find Malcolm's favorite birthday food we learn the royal navy is somehow still around in England even prior to the 2150s.

You'd think who would want to join the Royal Navy when you can join Starfleet or the earth cargo service.

What do you think?