The Hutus learned the lesson of what had happened in Somalia. They knew if they killed a few UN troops they would pull out. They lured a small group of Belgian soldiers into a building and hacked them to death stuffing their genitals down their throats. The UN began to pull out the next day.
The US citizens, pussified by their Somalia experience, did not want to be involved in anything that was not vital to US interests, and saw military use for humanitarian purposes as a terrible waste of US soldiers lives. The White House wore the "body bag" albatross around its neck for Somalia, got constant criticism from commentators and rival politicians, and was pussified too in the process. The UN, being the international body after all, should have been the spearhead of action, but disappeared up their ass after the Belgian killings. The US, pussified as it was, did not want to get involved without the UN taking the role of the primary responsible party for any action that the US might participate in. With the gross negligence of the UN, and the pussified Black Hawk Pussy nation of the US, the killings were unimpeded.
As the Middle East became more of the focus in the 2000s, several more African mass killings took place and we saw that the world had continued to be reluctant to be involved where killings take place within a sovereign country.