U.S. President Barack Obama (C) announces Jeh Johnson (R) to be his nominee for Secretary of Homeland Security, in the Rose Garden of the White House in Washington D.C., the United States, Oct. 18, 2013. Obama on Friday nominated former top Pentagon lawyer Jeh Johnson to head the Department of Homeland Security. [Xinhua]

U.S. President Barack Obama (C) announces former top Pentagon lawyer Jeh Johnson (R) to be his nominee for Secretary of Homeland Security, in the Rose Garden of the White House in Washington D.C., the United States, Oct. 18, 2013. [Xinhua]

Jeh Johnson (C), U.S. President Barack Obama's (R) nominee for Secretary of Homeland Security, speaks next to Vice President Joe Biden (L) in the Rose Garden of the White House in Washington D.C., the United States, Oct. 18, 2013. Obama on Friday nominated former top Pentagon lawyer Jeh Johnson to head the Department of Homeland Security. [Xinhua]

U.S. President Barack Obama (L) shakes hands with former top Pentagon lawyer Jeh Johnson, his nominee for Secretary of Homeland Security, in the Rose Garden of the White House in Washington D.C., the United States, Oct. 18, 2013. Obama on Friday nominated Jeh Johnson to head the Department of Homeland Security. [Xinhua]

Jeh Johnson (C), U.S. President Barack Obama's (R) nominee for Secretary of Homeland Security, speaks next to Vice President Joe Biden (L) in the Rose Garden of the White House in Washington D.C., the United States, Oct. 18, 2013. Obama on Friday nominated former top Pentagon lawyer Jeh Johnson to head the Department of Homeland Security. [Xinhua]