When Bush was running for president he needed to create a powerful alliance of insiders who were conservative to give him all that institutional power and influence. At the time, Project for the New American Century was an elite prestiguous conseravtive think tank with all the big names from within the military, intelligence, CEOs, politicians, etc... So to get their influence, he decided to offer them a deal, if he wins, he'll staff his administration with all these people and help them achieve their goals.

Now, what are these goals? Well they believed that future US hegemony was at risk as the world develops, so we would need to create a massively larger military - like significantly bigger and overwhelmingly powerful to stay far ahead of everyone. The problem was, Russia was gone, so Americans had no baddy to rally against to justify continued growth.

In 2000 they published their solution to this problem: Create a new enemy in the middle east which would enable a forever war, so we can continue building our MIC. The primary candidates were Iraq and Iran.

Once in office, 9/11 happened, and then Cheney worked in secret with the CIA to fabricate a narrative to justify invading one of these places, with the express purpose of creating an endless war. He also got the added benefit on no-bid contracts that enormous boosted his company's stock price - but that's besides the point.

The point is, Cheney intentionally fabricated a war he knew would last forever, because he didn't care if tons of people died if it meant we could justify increased military spending. IMO this is why weird, logic defying events happened in Iraq, like disbanding the Iraqi military. NO ONE thought this was a good idea, and defies all philosophy and research on the subject. As all it would do is flood the country with unemployed young people who were taught to kill... Which naturally leads to insurgency - but Cheney wanted that, because it helped keep the war going.