personal view:
the thing with japan is that after ww2 they got heavily disarmed ,they focused only on defensive military .
Now ,after the Ukraine war and the problems they face with China(and north Korea) they decide to increase the military budget ,just like everybody else "if my neighbor is buying a gun ,shouldn't I also have one ?"
Everybody says that we are at the start of the second cold war ,I tend to belive it .