The First 100: Days 91-100 (20 images)

U.S. President Barack Obama speaks to employees of the Federal Bureau of Investigation (FBI) at FBI headquarters in Washington on April 28, 2009. Obama told FBI employees today that confronting the threat of terrorism means the U.S. must adopt new tactics while still upholding its ideals. (UPI Photo/Brendan Smialowski/Pool)

President Barack Obama introduces the 2009 National Teacher of the Year, Anthony Mullen of Greenwich, Connecticut, during a ceremony in the Rose Garden of the White House in Washington on April 28, 2009. (UPI Photo/Kevin Dietsch)

Sen. Arlen Specter (D-PA) (C) speaks about his recent switch to the Democratic party alongside President Barack Obama and Vice President Joe Biden at the White House in Washington on April 29, 2009. Specter announced yesterday that has left the Republican party in favor of the Democrats bringing the Democrats within one vote of a filibusters proof majority. (UPI Photo/Kevin Dietsch)

Sen. Arlen Specter (D-PA) speaks about his recent switch to the Democratic party alongside President Barack Obama at the White House in Washington on April 29, 2009. Specter announced yesterday that has left the Republican party in favor of the Democrats bringing the Democrats within one vote of a filibusters proof majority. (UPI Photo/Kevin Dietsch)