The White House said Sunday it will end support for Kurdish forces in northeastern Syria and has ordered U.S. troops to step aside while Turkey begins a massive air and ground operation. The U.S. has about 1,000 troops in northeastern Syria; it’s not clear whether they’ll pull back to allow Turkey’s assault or leave Syria entirely. Since 2014, the U.S. has backed the Syrian Democratic Forces, led by the Kurdish People’s Protection Units, or YPG, in their fight against ISIS. A spokesperson for the fighters called Trump’s decision a “shocking and unexpected” betrayal. On Sunday, the White House said President Trump made the decision after speaking by telephone with President Recep Tayyip Erdogan.