The para military is just a form of business.
Think about it if you're a bomb maker or a quarter master in the U.D.F or I.R.A, what are ya gonna do now the struggle's over?
Sell second hand cars, get a job in Curry's?
You go into racketeering.
They had status during the struggles, now they're an anachronism, they're not going to fade away quietly so they perpetuate the old battles and make their living the old way, it's all they know.
It's almost perverse to think that it's as hard (if not harder) for an old provo to re-assimilate into society as it is for an ex squaddie.
At least being in Royal Artillery can be put onto your C.V.