Probably because current procedures have been updated many so times that these procedures wouldn't help anyone trying to launch a current ICBM. The article ment

Probably because current procedures have been updated many so times that these procedures wouldn't help anyone trying to launch a current ICBM. The article mentioned a voting system that's used to prevent modern ICBMs from being launched without the agreement of several launch sites. Also, notice the only computer mentioned in the place was the guidance system for the missile. I'm sure a modern ICBM site would have computer based security. An ICBM is useless if you can lockout the guidance system or detonator. Just think, the guidance system could drop the missile into the ocean or self-destruct the missile on lift off if it is somehow launched without proper codes. (Assuming you could get the rockets to fire in the first place) The warhead could refuse to detonate if the missile is launched without proper codes. There are many levels of security a computer can add to prevent an ICBM from being successfully launched. The Titan II launch procedures are based solely on mechanical security.