Agreed, we would have to cope. But because there are things that we can do (and things that would reduce our vulnerability to terrorism to boot), it's not a realistic or useful position to say "let's do nothing".
You may call my stance a "do nothing" approach, but it isn't. It simply suggests that it is possible to cope by trying to adapt rather than cope by trying to prevent. Particularly when, according to this very article, it's not preventable. Remember? Even if we reduce carbon emissions by 70% by 2050...? Up to nine degrees warmer by 2100, regardless? We can try to prevent the unpreventable or we can adapt. Sounds to me like adapting is actually much more rational.
Let's do nothing drastic; though we may well be in a position to lead in a sensible and workable program to conserve all resources, we still have an obligation to maintain the standard of living we have attained in order to help those still battling ancient diseases, deprivations and despotic rulers whose own needs are met regardless of the hardships they place on those they rule.