No ICBM's in the USAF inventory use GPS for guidance, too easy to jam as posted above. Some aircraft dropped bombs/missiles use it for guidance though.
The only reason that the Europeans have not embraced GPS is the old familiar tune....'not invented here'.
I am not a tin-foil hat wearing person but I believe the Euros really didn't like the fact that the USA could deny access to the system with the push of a button, one of the reasons for Galileo.