Really it's just logical thinking, well voiced, risk anallaized, but then the type of people we have to deal with aren't the type to read this, taking notes and being able to carry off such an act. Or for that matter thank god, being able to kill more than four Jewish people in a hold up in a Jewish supermarket during a six hour period.
The original plot to bomb the World Trade Center was close to an ideal. One big bomb in the garage, to topple one tower into the other.
The bomb was not big enough and I think only 6 died. Potential loss of life would be the full capacity 55,000 people.
2001 they returned to kill 2,977 people.
Fear of crowded places is well justified. It's for government to try and keep us all safe when large targets are available. That's the downside to atrocities. Minor team to kill 17, major team to kill hundreds, if not a thousand or so in a duck shoot or car bomb(s). So that means sharp shooters on vantage points and heavy vehicles to limit ingress into obvious areas.
I'm concerned that they had a grenade launcher. What mess would that cause to a 747 EL-AL flight out of Charles DeGaule airport?
Maybe another Air Malaysia, like the one just last year, lost over the Ukraine.
Beyond that, be quite scared by the USSR was said to have lost track of a large number of suitcase sized nuclear bombs. The PLO were said to have one of them, did they? And where is it now?