The civil war in Syria has grown more complicated since the United Nations General Assembly opened last month.
The five-year-old conflict began with a government crackdown on peaceful protests, fueling the growth of ISIS and creating a confusing array of alliances and a refugee crisis.
The turbulence is likely to continue since Russia sent warplanes into the country on Wednesday, giving the U.S. and its allies only an hour's notice. President Vladimir Putin told the U.N. earlier this week to back Assad in order to defeat ISIS.
The U.S. and its allies have not relented in their attempts to weaken ISIS through airstrikes on the terror group's positions in Syria and Iraq.
Despite all this effort, ISIS continues to grow, with an alleged 30,000 new recruits in the last year, and the U.S. is questioning whether Russian airstrikes are in fact targeting ISIS. Nearly 4 million migrants have fled Syria, with UN officials saying there's no end in sight for the humanitarian crisis.