FILE In this Dec. 1, 1994 file photo French U.N. soldiers point to an area from which four anti-tank missiles were fired, in Sarajevo, Bosnia. With the U.N. unable to agree how to protect civilians against Bashar Assad's forces, Western officials are discussing creation of safe corridors to deliver aid to Syrians trapped by the crackdown. Similar measures failed badly during the war in Bosnia two decades ago that killed over 100,000 people and left millions homeless. The lesson of Bosnia is that without all sides honoring the agreement _ and without a robust military response in case they don't _ such measures may have little effect and could actually prolong the misery. (AP Photo/Enric F. Marti, file)