VDH nails it in this article: his summary of the history of US involvement in Iraq is a devastating critique of the Democrats’ intellectual honesty.
Still, the whole idea of building an inclusive democratic republic in Iraq was a misguided waste of blood and treasure. I am unconvinced that Iraq was really on the road to such a republic before the American withdrawal, largely because such a republic is incompatible with any sort of Islamic fundamentalism.
Perhaps so, but irrelevant. If we had maintained our military and civilian presence there, we could have controlled any tendency towards societal and political disintegration. Hanson makes this very point in regard to post-war Japan and Korea in his article. I am not really concerned whether Iraqi society was "ready for democracy" or not -- it was (and is) in our national interest to have a stable, pro-western regime established in Iraq. We achieved that (at great cost in blood and treasure) and Obama threw it away.