They made available, former EOD techs, who were retiring from the services, to be hired. It was impressed on Cunard that this would be a good idea as the IRA were very interested in the QE2. During 1971 Bob Venning was the first. Shortly afterward quite a few Officers, myself included were given an extensive course on bomb detection by x-ray and baggage x-ray was started., It went on from there.
The article mentioned in the opening to this thread and some of the comments in it seem a tad misguided. YES, at some times the QE2 was in some hairy situations. But would Cunard willingly put 2800 lives in danger for money? I doubt it!