How does checking an ID stop him? It doesn't. And since the presented ID's are not being recorded and used to check against watch lists, for instance, the ID check is useless.
He is still going to detonate and kill people.
Well, we can be sure of one thing. If nothing is done, then there is a 100% chance he will detonate. I think common sense would tell us then the more that is done that the 100% would start to reduce. ID isn't the solution, it can be part of the solution..