Here's a good read from the Wall Street Journal; something to think about.
From Henniger, some of the reasons:
• Bush schadenfreude. Partisan pleasure in George Bush's pain dates to the anguish of the contested 2000 election loss. The Democrats have run against something called "Bush" for so long that this sentiment is now bound up in any act or policy remotely attached to the president. Iraq's troubles, or Iran or North Korea, are merely an artifact of crushing this one guy.
• The Iraq Study Group. The ISG report wasn't defeatist, but it enabled the vocabulary of defeat. Its warning of a "slide toward chaos" was re-defined as the current Iraqi status quo. They called their bipartisan solution "phased withdrawal," but it was a euphemism for defeat. Momentum was already building in this direction, and the ISG propelled it.
• The leadership vacuum. The administration never rallied the nation behind the war in a concrete way. A young Marine officer recently returned from combat in Iraq told me this week he is taken aback at how disassociated the American people seem from Iraq, no matter how constantly it's in the news. He says it's as if the problem is not so much what is actually happening in Iraq but that the war is "annoying" to Americans, as if to say: Can't it just go away or not be on the front page all the time? Rallying a nation at war is a president's job.
• The opposition vacuum. One reason the negative mood in politics is so disconcerting is that the opposition's alternative vision is nonexistent. On joining the opposition recently, GOP Sen. Norm Coleman announced, "I can't tell you what the path to success is." Joe Biden says the "primary" Iraq strategy should be to force its leaders to make the political compromises necessary to "end the violence."