President Barack Obama greets FBI Director Robert Mueller after Mueller introduced him to speak to FBI employees at FBI headquarters in Washington, Tuesday, April 28, 2009 U.S. President Barack Obama smiles as he puts on a cap given to him by FBI director Robert Mueller during his visit to FBI headquarters in Washington April 28, 2009. U.S. President Barack Obama receives teddy bears as a gift for his daughters from FBI director Robert Mueller during his visit to FBI headquarters in Washington April 28, 2009. President Barack Obama delivers remarks to FBI employees at FBI headquarters in Washington, Tuesday, April...