Missle delivery systems are doubtful.
They could be in Canada, Mexico or even in the US.
The problem is retaliation. Who do we target?
Terrorist cells are known to be in this country.
All they have to do is get a paneled truck and drive it into NYC or DC and activate it.
Why one hasn't one gone off yet?
Well, it could be the lack of a proper arming device.
When you only have one or two of these weapons you can't afford to waste them.