Johnson could have chosen not to start the War in Vietnam.
Nixon could have left in a much more timely manner.
Reagan could have chosen not to invade Granada.
Bush the Elder could have chosen not to fight Iraq.
Bush the Younger could have chosen not to simply go after Al Qaeda, and nothing else.
Obama could have left Iraq and Afghanistan within his first year in office.
None of this is that simple and you know it.
It seems pretty simple to me.
Notice how China, a very powerful nation, doesn't feel the need to intervene everywhere. Neither does Russia or India.
Ukraine and Georgia say hi. What's that? Andhra Pradesh, Bengal areas, Bangladesh, Sri Lanka, said what's up.
They intervene near their borders. They aren't intervening in conflicts in South America though.