Obama, wary of foreign crises, faces East-West standoff in Ukraine

U.S. President Barack Obama (L) greets supporters after addressing the winter meeting of the Democratic National Committee in Washington February 28, 2014. REUTERS/Jonathan Ernst

WASHINGTON (Reuters) - As Russia deepened its military intervention in Ukraine's Crimea region on Saturday, ignoring Barack Obama's stern warning, the U.S. president faced a critical test of whether Washington has the leverage or the will to get Moscow to back down.

Obama, who has avoided entanglement in global crises where possible and focused on domestic affairs, now finds himself in the midst of the most dangerous East-West standoff since the end of the Cold War.