Now, of course this would not result in a happy-go-lucky, hunky dory, lets all hold hands by the campfire and sing Kumbaya together world. In fact this might result in a less peaceful world, however I would actually like to know if the United States of America began massive interventions similar to the Gulf War in the '90s humanitarian hotspots.
Think about in 1994, by April 20th the USA calls the Rwanda situation a genocide and sends in troops and tries to organize a coalition of the forces of the world's developed nations to go into there and try to make peace.
I would like to be realistic. There will be ripples if the USA stays in Somalia, goes into Rwanda, puts more troops into the former Yugoslavia, and expands the operations in Haiti, I just want to know what they are to live in a realistic world.
How do you get sufficient forces, with decent support into Rhwanda? The country itself is landlocked, meaning the normal naval flotilla is of little use. You will have to fly in every bit of transport, every bit of supply, everything. You get to do that to a country with ONE runway capable of handling C-141 & C-5 cargo aircraft. There MAY be worse places to get to with substantial numbers of troops, but not very many.
Solmalia? What would the point be in staying? To ensure that the country was peaceful and safe the U.S. would have been forced to kill at least 10,000 people, maybe more depending on how hot the population got over the effort.
Yugoslavia was a train wreck. How do you keep people from killing each other over something that happened a century before?
Just these three train wrecks, which are far from the only ones going at the time, would soak up 300,000 troops, if not more, and would put U.S. troops into situations where everyone was shooting that them. To end all the crisis, just in sub-Sarahan Africa, would take at least a million men and would cost more lives every year than the last six years in the Sandbox.
You can NOT make people love their neighbors at gunpoint. You either stay forever and are called either occuppier or imperialist (with more than some truth) while you keep the two sides apart, or you stay until you can justify the losses. The minute you leave the bloodletting begins just like you were never there.
To actually change things, especially in Africa, which is the current area of greatest conflict, you would have to totally redraw the map based on tribes or clans. Even then you will have massive issues with creating a viable political division. For whatever reason (blame European occupation, or communitation difficulties or terrain, or $%#^ happens) most of Africa doesn't fall nicely into "states" that make any sort of logical sense.
Expect the U.S. to deploy a million men, for, at the least, decades just to keep the lid on long enough for some of the political divisions to take root?
Good luck.