Tensions Rise between Pakistan, US Military on the Afghan Border

If American troops cross the border into their country, Pakistan's military has been ordered to fire. Admiral Mike Mullen, chair of the US Joint Chiefs of Staff, is in Pakistan where there's confusion over whether American helicopters were fired on hear the border with Afghanistan. Both countries deny reports that such an incident has already occurred. Stephen Cohen, a former member of the Policy Planning Staff at the State Department, is and author of The Idea of Pakistan.