To answer your question though, diplomacy is certainly good and should be the first choice. But it's not "inherently good"; just ask Czechoslovakia how they felt about Chamberlin's diplomacy with Hitler.
More to the point, nations have to live with the results of their diplomatic efforts, so it's important that those efforts are attuned to work together.
If you were a CEO trying to shift company strategy to focus on a certain goal, you'd find it at least annoying if a former CEO went out and directly worked against that strategy because they "had a better way to do it". Even worse, being pulled in both directions could end up leading to a worse outcome for that company than if one or the other solution had been chosen.