The terrorists hoped that these attacks would send the entire civilization into the death spiral.
And they were right.
Almost all of the surveilance/security theater/thought police/war on terror bullshit we're dealing with today everywhere in the world, can be traced back to that very morning in New York.
The whole "anti-terrorist" shebang scored way greater body count than the attacks themselves, all of them, combined. Not to mention trillions and trillions of every currency under the Sun, that could have easily lifted the entire humanity out of poverty, eaten by the military industrial complex instead.
It's like we're in a bad timeline. I was alive to see it happen, and the world has never truly recovered from it ever since. Instead, it just collapses ever deeper into self-perpetuating self-consumption. This sucks. I hate this so much.