The White House's counterterrorism adviser says he's seen no evidence that the controversy over building an Islamic center and mosque near ground zero is fueling terrorism against the U.S.

Some commentators have suggested that opposition to the mosque could gin up sentiment among U.S. enemies, complicating counterterror efforts.

John Brennan made the comment Friday in response to a question at the White House press briefing held on Martha's Vineyard where President Barack Obama is vacationing.

Brennan said that terrorist groups would point to a number of reasons for their activity, many of them unfounded.