Some people in the blogsphere are speculating that Bush's "Bring them on" statement was meant to lure terrorists to attack US forces in Iraq. The idea is that if they're drawn to attack our military forces (where a good percentage of them are quickly killed), they aren't able to conduct terrorist attacks elsewhere. Yes, such a strategy would increase the casualties for our forces in Iraq but it would be more effective and less dangerous than going after the terrorists in their home turf.

Of course, this is all speculation but stories like the one you linked are consistent with the flypaper theory.