Obama - countering violent extremism depends on Muslim support

By Julia Edwards WASHINGTON (Reuters) - U.S. President Barack Obama on Wednesday called on American Muslim communities to do more to counter what he called "violent extremism," speaking at a three-day White House summit on the issue. Critics have accused the White House of shying away from tying extremism to the religion of Islam following shootings by Islamic militants in Paris and Copenhagen. "Muslim leaders need to do more to discredit the notion that our nations are determined