Well: https://en.wikipedia.org/wiki/War_Is_a_Racket

From 1935. And he was not the first one to point that out either.

I actually think that thanks to the internet, we expose many more criminal build ups towards warfare nowadays than before.

Eisenhower's farewell speech [1] is also basically prophetic, which is quite unfortunate in that they were all warnings of things to vigilantly avoid.

[1] - https://avalon.law.yale.edu/20th_century/eisenhower001.asp