Special Report: Obama says U.S. won't back down in the face of ISIS atrocities

An emotional President Obama addressed the beheading of American journalist James Foley by the terror group ISIS from Martha's Vineyard Wednesday afternoon, vowing that that the United States will be "vigilant and relentless" in its efforts to protect Americans in Iraq, and would make sure that justice is done. Scott Pelley anchors this CBS News Special Report, with Major Garrett reporting.