First of all, it's no more our business than it would be Russia's if the US decided to invade Mexico because south America was enticing them into an alliance to counter US interests.
The USA as the global policeman is as outdated as was its involvement in Korea and Vietnam. Both were disasters and life-suckers that had no practical value beyond SHOWING STRENGTH!!! and SENDING A MESSAGE!!! Last I checked, North Korea is still there decades later and is as primitive as ever. Vietnam, decades later, is developing as a sort of hybrid authoritarian state...China-like model. What did the US really do there? What are the nuanced influences as to how geopolitics and the cold war played out over the remainder of the 70s and 80s? Fuck if I know.
And since, the US's police-action stuff has been equally life sucking bullshit. One after a fucking another.