And by spraying markers on a lot of people you can either:
- cost a lot of money by forcing events to be cancelled;
- enforce more invasive/costly security measures;
- diminush the value of the security mesure and pass a bomb in.
But this is what's strange with terrorists : they strike ma as utterly incompetents. There is so many easy ways to fuck things up, and they always do the ineficient and hard things. My father worked as a head of security for a national company, we used to discuss of all the way you can really hurt companies, people and society. It's not even that hard and costly. Are they lacking of imagination, or not really trying ?
Every-one thinks that they are the good guy. That isn't just a quirk of psychology, it is also a constraint.
People lives their lives according to different narratives. There is a fire-and-sword Muslim narrative, a quiet-life Muslim narrative, various Western narratives. Some-one living their life according to the fire-and-sword Muslim narrative is a bad guy by many other narratives. But that doesn't liberate them to be a bad guy by their own standards. They still have to be the good guy in their own head.
They have to be the hero, not the ass-hole. They cannot just be a nihilist who wrecks stuff to make things miserable for every-one. There has to be a sense that they are a warrior, fighting bad guys.
Perhaps it is as simple as attacking a cafe where they serve alcohol or a venue where the music is haram, or a business district where they charge interest on loans. I don't really get the inner logic, but I'm sure there is one and it constrains the kind of attacks they can make.
I made this argument years ago, if you want to weaken a population and cause maximum disruption go after infrastructure, a lot of it isn't guarded by more than a chainlink fence and is out in the middle of nowhere (electrical sub-stations been a good example).
Modern society is incredibly dependent on lots of complex systems with moving parts all functioning at high capacity, it wouldn't take a lot to get things wobbling.
I don't think that intelligence is in any way correlated to having worldviews of most of modern terrorists. Just compare their methods to Unabomber, for example.