I’ve just read a few things online. I know of the “coup” attempt and of his book, “War is a Racket”. I’m not so sure of the details of his exploits, just that he left the Military dissalusioned and feeling that he was just an arm of corporations and financial interests. I believe he put it a “gangster for capitalism”.
My thoughts are similar to Butlers. War or military intervention usually leads to some kind of profiteering, resource pillaging or regime change that is more “sympathetic” to US business interests. What really threw me with Butler was that this sort of thing went on that far back. I had always assumed it started after WWII because of huge amounts of money that built, as Eisenhower put it, the “Military-Industrial Complex”.
You should look into John Perkins, who wrote “Confessions of an Economic Hit Man”. He is the other side of the military equation. He would go into third world countries and try and bribe leaders. If he failed they would send in what he called the “Jackals” to assassinate them. If they failed then the military would eventually go in.