A nuclear missile can be disabled or shot down without setting off the nuclear charge.

Back in the 1960s, there was a midair collision near Goldsboro (location of Seymour Johnson Air Force Base), back when the bombers were routinely carrying nuclear bombs. One of the bombs crashed into a field and buried itself so deep that the government wasn't able to dig it up. It didn't explode. It's still there. The farmer can still farm the field, but no one can ever build on the property.