The sinking of a presidency

This is getting rather repetitive, isn't it?

Here are the latest numbers: "Growing dissatisfaction with the war in Iraq has driven President Bush's approval rating to a new low of 36 percent, according to a CNN/USA Today/Gallup poll released Monday."

As for Iraq itself: "Only 38 percent said they believe the nearly 3-year-old war was going well for the United States, down from 46 percent in January, while 60 percent said they believed the war was going poorly. Nearly half of those polled said they believe Democrats would do a better job of managing the war -- even though only a quarter of them said the opposition party has a clear plan for resolving the situation."

Since it's already repetitive, let me repeat that:

Bush's approval rating stands at 36 percent.

I realize that there is a tendency to place far too much emphasis on polls, which at best measure transient and usually fickle public opinion, but, looking back over 5+ years, can we not with confidence conclude that Bush has been a failure?

Or is there some nuance to Bush's astonishing unpopularity that I'm missing?