How To Know When The War On Terror Is Over

How will we know when the 'war on terror' is over?

I would think that by the phraseology of war on terror, the efforts to contain it, it will never be over. It will never be over because terrorism by the true nature of what it is morphs into something new all the time. What's interesting about terrorism is that the groups that are successful, like Al Qaida, which by the way is going to celebrate its second decade of existence next year, they're successful because they're able to adapt, be flexible and learn. They're a learning organization, so if they learn how to compromise our security efforts, that war will never end. It may subside, it may be reduced in terms of frequency, but we'll never be comfortable to the point where we can believe it's over.