> Bringing democracy to Iraq was never a stated goal of any US administration.
From Bush's speech: "A campaign on harsh terrain in a vast country could be longer and more difficult than some have predicted. And helping Iraqis achieve a united, stable, and free country will require our sustained commitment. Yet, whatever is required of us, we will carry out all the duties we have accepted." (emphasis mine, http://georgewbush-whitehouse.archives.gov/news/releases/200...)
But either way, let's take it as true, the Bush White House was not exactly consistent with regarding to the reasoning for invading Iraq at any point.
However, bringing democracy to the countries affected by the Arab Spring wasn't always the stated goal either, no? At least for Libya, Syria, and Egypt the issue was the corruption of the then-current government. Although in all of those cases the end result appears to be on track for some kind of democratic state, it's not looking very promising in Egypt IMHO. And who knows where the ruins of Syria will end up?
> If Iraq had a true democracy they'd nationalize the oil fields
Well Big Oil was doing just fine before the U.S. invaded Iraq, and in general seem to do better when Islamists aren't blowing up their pipelines. So while I "rah rah bad corporations" too I'm not quite to the point where I'm willing to pin all geopolitical maneuvers on what's best for Exxon-Mobil.
You're exactly right that Iraq is potentially in a better position to force re-negotiation of oil contracts than Saddam's Iraq was; they could simply buy off the puppet. So maaaybe we should be careful about all the accusations "Blood for Oil" for Iraq in 2003, as the war made no sense at all from the perspective of Western oil companies.
Even now I have no clue as to why Bush actually invaded Iraq but I don't think it was oil. Even if it was somehow much easier for American companies to get access to Iraq's oil after a protracted occupation, it wouldn't be worth the capital (let alone human) cost overall even for all the oil in Iraq. Even if Bush didn't know that, all his oil friends that he was buddy-buddy with could easily tell him.