"A huge exercise was launched across government, intelligence agencies and policing to identify new measures to stop atrocities after five attacks hit the UK in less than six months." And having 'identified' an atrocity in the making? Then what?? I don't think anyone's thought of that bit! Gesture politics and pointless spinning is all this risible excuse for government is capable of. https://www.mirror.co.uk/news/politics/mi5-police-faster-tip-offs-12643798
I think the idea is to alert the security forces about suspicous purchases so that they have the ability investigate and act accordingly...makes sense...but as you say it's dependent upon what actions in law they can take.
Exactement! My solution is that if they intended to carry out an atrocity then they should be prevented from doing so, and there's only one way to ensure that? The point is they're on a win, win, and win - if they escape they live to kill another day, if they're caught they spend a few months in one of HM's holiday camps, and if they're shot dead, well hey, that's what they want anyway?