Syria poses challenge for new US envoy at UN by By LARA JAKES WASHINGTON (AP) -- Fiery human rights advocate Samantha Power has famously taken presidents to task for refusing to use military force to stop genocide. But as the U.S. ambassador to the U.N., Power may need to bite her tongue as the Obama administration resists being drawn into Syria.. hosted.ap.org/dynamic/stories/U/US_POWER_PROFILE?SITE=NYWNE&SECTION=HOME&TEMPLATE=DEFAULT