These groups are linked they know each other, members in SF know who these people are and do not do the right thing and report them to the proper authorities. They are letting these people run around trying to murder those they want to represent.
We hear how such and such an inquiry is doing this that and the other to bring those who colluded with whatever terrorist to justice. Should the same action not be taken with regards to the IRA and it's spin off's?
One point though the simplistic bomb could indicate a lack of supplies, two pipe bombs and petrol rather than semtex.