You're not even reading your own arguments, near as I can tell?
Of course a dirty bomb isn't militarily useful to the US gov't. They have literal nuclear weapons. Hijacking a civilian airliner and using it to attack a target in a suicide attack ALSO isn't militarily useful to the US government. They have cruise missiles.
They also wouldn't stoop to these kinds of tactics, and have overpowering force in other areas, so what else is the enemy going to use (eventually)?
A tiny group (equivalent to a US Army Company in size) being able to attack one of the most prominent financial centers of the United States successfully (and, notably, the Pentagon as well!) on live TV, instilling fear and terror in the populace, and even getting away with it for a decade is of course an existential threat to the United States.
Near as I can tell, no country in the world could pull that off successfully, not even Russia or China.
And how do you propose the gov't was going to 'just arrest' Osama Bin Laden? Or any other terrorist group?
The whole point is that they hide among civilians and go deep underground when hunted, using what we won't do to be successful.
It took a decade to even FIND OBL. And if they put him on trial, it would just give him an audience to push buttons and get his message out even wider and stir up more shit. Look at what is going on with Israel and Palestine/Hamas.
And how would you propose that the gov't not have the populace scared when something like 9/11 happens.
Should the news just not report on someone plowing nearly fully occupied airliners into the iconic and fully occupied World Trade Center towers in downtown Manhattan, or the Pentagon - in broad daylight during a workday, no less.
Towers that were common tourist hotspots and were plainly visible literally from some of the busiest streets in one of the most prominent cities in the entire world?
With no warning, and no effective countermeasures or prevention at the time?
Or that the entire US picks up deep meditation practice to understand the futility of 'holding on' to such things and how they get used against oneself?
Neither of those are realistic, or even a good idea near as I can tell in this situation.
Honestly, this type of attitude is exactly what leads up to these kinds of situations happening. It's sticking one's head in the sand.
And the world isn't slowing down. Check out this 3D printed surface to air missile project on Youtube.
[https://www.youtube.com/watch?v=UvcDwSmmxWs]
And this little piece on the Glock Switch, which has been circulating for years. Also easy to make at home with a 3D printer, a vise, and a file.
[https://www.youtube.com/watch?v=DfVKcItEaiE]
I'm done wasting my time in this discussion now.