Former Afghan general says chaos at Kabul airport was "the worst situation of my life"

As the world marks five years since the U.S. troop withdrawal from Afghanistan, former Afghan General Haibatullah Alizai tells "Face the Nation with Margaret Brennan" that as he looks back at the chaotic withdrawal, it is the "worst situation of my life," adding that he was thinking of the families of his friends who were killed and "I didn't have any answers for their families at that point."