Some of the modelling from the US show that it takes a lot of bad news to dump an incumbent President, more so 1st time around for a Republican. Using the 3 factors of economy (expressed as growth), inflation and good/bad news it would take a scenario of -2.5% growth, 6% inflation and no good news to take GW out. Even with 2.5% growth, 2.5% infaltion and no good news he will get back.
These factors apply to the election year only hence the pressure to get Iraq out of the way.
So it would appear that it would take an awful lot of worse than usual domestic economic data to shift GW. Any terrorist attack on the US real or imagined will only strengthen the incumbents position.
