Rare back-to-back bombings in the capitals of two nuclear-armed neighbors are threatening to send India and Pakistan to the brink of conflict for the second time this year, as tensions also soar between Pakistan and Afghanistan . India is describing the car explosion that struck Delhi on Monday, killing at least eight people and injuring 20 others, as a “terror incident.” Authorities say they are investigating the explosion under an anti-terrorism law and considering “all possibilities.” “The