Agree in the last sentence, the thing is as Dirtboy said some people are abusing of the war tool, ergo, IMO they are the tyrants which you must fight against. There was only one Hitler, the rest, the inmense rest of wars (Vietnam, Korea, Kosovo, Africa, Lybia, Israel, interventions as Guatemala, Granada, dictatorships all over the western hemisphere) the huge inmense majority of interventions were not against Hitler, (some) there were against democratic governments. So in some level you must believe in these actions/interventions to provide your body.
Let us not forget, that the wars in South Korea and South Vietnam were to defend these two countries against invasions from North Korea and North Vietnam.
South Vietnam became a stinker because of timid politicians and ended by South Vietnam being conquered by North Vietnam and forced to become communist.
How would you like to live in North Korea? The South Koreans don't want it either.
Guatemala was a stinker, but it was not a US invasion as such, it was a CIA operation planned and performed by a corrupt US secretary of state, John Foster Dulles, who together with his corrupt brother, CIA Director Allen Dulles, had been working for a law firm with close ties to United Fruit. Helped by the anti-communist doctrine current at that time they pursuaded Eisenhower to support a
exile invasion. Here I've got you in a cleft stick, Matias, because had Arbenz let the Guatemalan armed forces fight it out, they would have won easily, but he chickened out instead of defending what he believed in.
Granada was probably a stinker (difficult to assess, political case).
Africa?
Libya: The Libyans were undoubtedly happy to live under their Great Dictator, that's probably why they rebelled and started a civil war.
Elsewhere in Africa: Is it OK to let e.g.the Arab population in Somalia slaughter the black population?
Damned if you do, damned if you don't.
Stay away from Africa!!! Why didn't you intervene in Africa???
Israel - let's see: The only democracy in the Middle East, created by a unanimous UN decision, these past 15-20 years doing its best to lose support from the rest of the world. How would Argentina treat Uruguay, if Uruguayans fired a couple of hundred rockets into Argentina every month?