"Barack Obama has abandoned America at the place where America's heart was broken nine years ago, and where her true values were on display for all to see," said Debra Burlingame, a spokeswoman for some Sept. 11 victims' families and the sister of one of the pilots killed in the attacks.

Building the mosque at ground zero, she said, "is a deliberately provocative act that will precipitate more bloodshed in the name of Allah."