It may be 12 years ago, and if it were a normal tragedy like a hurricane, earthquake or volcano, then it would still be a painful memory but you'd get past it. Natural disasters are innocent. This wasn't. It was malicious, and the attitudes that drove it still exist. It's tough to reconcile. Then, it's not helped by the fact that the attack was irrational. There's little defense against that sort of thing. When an adversary is unreasonable, there's not much to work with. Makes it extra-scary, and makes it tough to lower your guard. Especially when the threat is ongoing.
For as hard as we hit back after 9/11, it wasn't nearly enough. The targets were probably wrong, and the real problem was a lack of will to exert as much force as was needed. The only way to win a fight is to either eliminate your enemy altogether, or overpower them to such an overwhelming degree that they lose their will to fight. We did neither. We never do. Somehow, all we do is spend money we don't have making a mess of things, then even more money fixing it after the fact.
If it was me in charge of the most powerful military dog in the world, I'd be mighty cautious about unchaining the thing. But, once it got to that point, let the pros handle it. Get the politicians out of the way. Tell the dog to sic 'em, and stand back. Wouldn't take any time at all, and the problem would be solved. Then, let whoever's left rebuild however they want. I wouldn't help them wipe away a single tear. They screwed up, it's up to them to reconcile, not us.