Complicity.

They are on Bush's side, not on the side of the voters. 3% of Americans approve of how Congress is handling the war in Iraq. How much more obvious does it need to be?

They have some fear, but not of Bush:

They are afraid that the US economy cannot and will not continue to dominate the world economy, and will collapse, unless the US is able to dominate the energy resources of the world, and that cannot be done if the US withdraws from Iraq.

when Bush says, "Even if you thought it was a mistake to go into Iraq, it would be a far greater mistake to pull out now," he's expressing a fear -- from an imperialist viewpoint - that a U.S. pullout would leave the empire weaker. And he is saying this in opposition to other forces in the U.S. ruling class who, also coming from an imperialist viewpoint, now think it's a big mistake for the U.S. not to withdraw.
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This whole dynamic of riding the anti-war vote to power, then voting to fund an ongoing war while claiming to be ending it, reflect the conflicting necessities the Democrats face. As representatives of U.S. imperialism, they are committed to maintaining U.S. global dominance. Yet they fear the U.S. is sliding toward a strategic debacle of epic proportions and may already have lost the war in Iraq.

The evidence states that Democrats are basically on board with Bush.
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If Democrats were filled with fear that they would lose Congress and the presidency UNLESS the occupation was ended before the 2008 elections, they would end the occupation of Iraq.

Their thinking is a$$-backwards and causes the problems they think think hegemony and imperialism will solve.

If the "empire" falls it will be because insanely misguided attempts at preserving it like invading and occupying Iraq produce the opposite result.

You Must Be Mad, Or You Wouldn't Have Come Here

One of the legacies of six years of the George W. Bush Administration is that America has gone "From $20 trillion in fiscal exposures in 2000 to over $50 trillion in only six years

The US is insolvent.

That is the conclusion of a recent Treasury/OMB report entitled Financial Report of the United States Government that was quietly slipped out on a Friday (12/15/06), deep in the holiday season, with little fanfare.

That fear needs to be replaced with another fear.

They would notice if enough people turned the tables on them and used fear to motivate them, instead of voting simply out of fear of republicans.