Iowa looming, GOP candidates go on the attack in debate

Aired: 1/15/2016 | 0:04:09 | Clip
Donald Trump and Sen. Ted Cruz dominated Thursday’s Republican presidential debate in South Carolina, swapping testy swipes over Cruz’s birth in Canada and Donald Trump’s hometown. Meanwhile, Gov. Chris Christie and Sen. Marco Rubio saved their toughest words for President Obama. William Brangham reports.