Seeing as we do the whole net centric thing so well these days, witht he advent of killer UAVs etc, what would be wrong with those Gimpy/minigun/40mm auto grenade launchers aimed with CCTV and monitored via satlink? as soon as we are within ROE, the military could engage targets from the tanker. The tanker companies could cover the install and maintainance cost, governments the manning and ROE, the pirates get wasted.
I have seen CCTV aimed weapons all over MRAP, all it takes is the "next step", IE satlink to the CCTV and weapon aiming.
Would seem to solve a lot of problems and means you dont need the boots on the ground to drill 7.62mm holes in these F*ckers. Skipper could even have a panic alarm.