...will be the things that crack this.

The structure you described in your post, above, is a structure more in line with organized crime than with a hostile nation.

War is waged upon nations. War is loud and flashy, and comes with lots of burned-out buildings, wrecked water and electrical systems, and dead children. We have been spoiled by WWII into thinking that wars are just, and that the outcome is good, because in that freak war those things were true. Actually, most wars are more like the Civil War and WWI: lots of death, grief and destruction for everyone, and the only good to come from it is legislated afterward anyway, to the resistance of the losers with whom there eventually has to be another struggle.

Criminal organizations are taken down by infiltration; arrests, sometimes accompanied by shootouts with SWAT teams, the militarized part of the police; forensics; and the very unglamorous field of accounting, to trace money laundering, fraud, and so forth, in order to cut off the money. There are occasional problems with destroyed buildings and dead children, but nowhere near what you get in a war, and everyone's water and lights remain on. I agree that in Afghanistan, you have a clear case for a SWAT team, and there had to be a damn big one, so the international community got together and sent one. It takes a long time to bring down a criminal organization, there's very little bang and flash for the cameras, and there will always be more (if different) criminals, but there you go.

Nobody has ever invaded the Bloods. The Bloods are now a national organization, and though it might be possible to target their neighborhoods, the other casualties would be too much for the citizens of this country to bear. We don't call out military strikes against our own people, yet we seem to think that the results in other nations would somehow be different than, say, dropping precision bombs in Los Angeles. I think we feel more comfortable waging war abroad because those other places are far away, but that's my opinion.

Nobody has ever invaded the Mafia. The Mafia is far more established and sophisticated, has moved into the mainstream, and has lots of resources to which a street gang like the Bloods has no access: in many ways, a lot like the terrorist groups with their money and their front men, and their fraternal organizations. They do a lot of damage. Yet we go after them, very effectively, with accountants and wiretaps, and chip away at their organizations. Why? Because we don't want revenge: we want them to stop, and on our terms, not theirs.

There's a big difference.

Now, about these terrorists: sure, they say they want to destroy us. I believe them. They have very grandiose ideas and an extremely high opinion of themselves. I can't speak for anyone else, but their inflated egos and insane ambitions don't impress me, though I do think we must take some counteraction because they are destructive. So: do we want revenge, or do we want them to stop?