U.S. troops leaving Afghanistan teetering on the brink of all-out civil war

Kabul — U.S. officials have said the withdrawal of American troops from Afghanistan will most likely be finished by July 4. Behind them, they'll leave Afghanistan's own security forces struggling to defend their country from a brazen Taliban offensive.  

CBS News correspondent Charlie D'Agata went to the front line in the still-raging war this week with Afghan forces. The battle is just two hours north of Kabul, and it's drawing nearer every day. D'Agata has covered the war in Afghanistan for years, and he's been to the front line many times. But while getting to the fight from Kabul used to mean hitching a ride on a helicopter, for this visit, it was just a drive into the mountains right outside the capital city.