When Assad fled Syria, shocking the world, President-Elect Trump made his thoughts clear on the region. In short, he said "stay out, America." But can the world's most powerful nation afford to ignore Syria's uncertain future? This is a good news story, says US national security advisor Jake Sullivan, that could turn bad very quickly.

"The minute Damascus fell, ISIS began to look for any opportunity it could take to reconstitute, grow, spread, and ultimately recreate a platform from which to threaten the United States and Americans around the world."