Korea at least I can understand - there is still a threat from DPRK, and being in Korea also binds Japan to the USA.
What I can NOT understand is being in NATO. NATO was designed to fight the Cold War, which ended 20 years ago. So instead of disbanding, they expand their role to “global cop” and guarantees the security of 35+ nations. The Germans and French can pay for their own security.
The Germans and the French won’t stand up to increasingly re-invigorated (and frankly, fascist leaning) Russia.
If we are not the major player in continental Europe, Russia will be.
What we should do is stay in these places...and (somehow) make them pay for our peace-keeping there.
I think we are more in NATO to keep them from going at each others throats and to keep the chins from exercising hegemony over that part of the pacific. I also think that the SK military would love the chance to go in and wipe out the NK army and kime. But the chins don’t want a unified Korea because that would put them between two strong economies.