Both last terrorist attacks were really amateur. Not that they did not achieve their point but these were amateur... Disposable people were used to this. Now, something I don't get comes from the background of these guys: one was a known "sinner" (rich bisexual life, substance abuse, etc.) whilst the other, a refugee from Afghanistan who had his own room in his foster family's home was being integrated since 2 years.

What don't get is how these people can remain under the radar until they do their trick?

Then it kinda hit me: what if, like "Au bonheur des ogres", "the bomb was built in place"? What if these were lambda people programmed to do their duty then dispose of themselves before they land back in reality? Even for decent developers, this kind of programming cannot be reverse-engineered without samples. That's why I think it's vital these people are captured alive because they've got to talk, we've got to find whoever get them to achieve their dirty jobs and get away with it.