In Iran, America initially supported the government of Prime Minister Mohammed Mosaddeq, even as it attempted to nationalize the British oil fields upon which Britain depended critically for post-war reconstruction. Britain told America it would not be able to assist in the organized defense of capitalism against Russia without the oil revenue, so America swallowed its anti-colonial pride and performed its first major CIA coup, an action for which it is still paying dearly today. In Vietnam, similarly, France informed its ally in Washington that it simply could not both defend its Southeast Asian colonies from communism and support the effort to defend western Europe. America, again, swallowed its anti-colonial rhetoric and marched down the path toward another costly scar for which it is still paying dearly.
Both are evidence of American commitment to strategic international purposes even where rhetorical discourse, domestic support, and even common sense would say to stay out of a fight. I'll tell you who I'd pick for my team if I was trying to convince anyone to think twice before treating me rudely.