1. The difficulty can't increase by more than 4x per 2016 blocks, as a measure against exactly this sort of "attack".
2. The "attack", as others pointed out, would cost several million dollars.
3. Even if you did succeed, it's not clear what harm you would have done. You would have a lot of bitcoins and new ones would come into circulation more slowly. If you held or destroyed your bitcoins, the resulting shortage of new money would lead to an increase in the value of bitcoins. Come to think of it, I kind of hope someone tries this "attack".