most people think that the Iraq War is part of why the economy is tanking.

I don't think there can be any doubt it's part of the problem. The only room for argument is over how much of the problem it is. The war roughly doubled the price of gas, after all. Also, by driving up the public debt, it reduced foreign confidence in the dollar, which has driven down the value of the dollar and driven up the price of imported goods.

Oh, and the war, and Bush's menacing stance toward Iran, inspired Iran to start selling oil in euros, which further weakens the dollar.