Why did the Iraq War go on far longer than the Bush administration expected it to?

Answer 1

It did not go longer that expected. Our government is now waging continuous wars.

Answer 2

Bush, Cheney, and Rumsfeld expected the war to end within a few weeks of the initial invasion. They held the entirely unreasonable expectation that Iraqis would embrace the American soldiers as their saviors for overthrowing Saddam Hussein and would immediately come together in a perfect American-style democracy. As would be expected by anyone who knows anything about the Middle East, the Iraqis saw the American soldiers as an occupying and colonialist force. Numerous paramilitary cells of different Iraqi warriors rose up to resist the American soldiers prolonging the conflict for nearly eight more years. Since US withdrawal in 2011, the insurgency has continued and the Iraqi National Government has expended numerous resources to attempt to quell it.