Move seems to be in retaliation for morning's helicopter strikes
                                
                                
                                    (Newser) -
                                    Pakistan blocked a major NATO supply line into Afghanistan today, in apparent retaliation for a cross-border helicopter attack. A pair of NATO helicopters opened fire on a border village in Pakistan’s Kurram region this morning, killing three Frontiers Corps troops, Pakistani security tells  Reuters . Within hours, roughly 100 NATO...