Tactical nukes were present during the Cuban Missile Crisis. Each Soviet sub had a tactical nuke torpedo for use in blasting US ships out of the troposphere. Fear of a conventional conflict going nuclear is one of the things that got JFK to cool his jets when his advisers where champing at the bit to invade Cuba.

Pakistan has been a problem since it was created as a wedge to divide the Indian sub-continent. It presents more of a threat to regional stability in that part of the world than any other nation. A significant degree of that threat can be chalked up to American foreign policy.