They show there was significant tension between the civilian administrators and the military commanders who wanted more resources, and that there was little planning for the post-Saddam situation. In fact, the unit set up for post-war planning was only created in February 2003.
Other documents show friction between the British and American military commands, particularly over the British forces’ refusal to take action against Shiite militias under the leadership of Moqtada al-Sadr in the south and the decision to engage in dialogue with them instead.
Regardless of your feelings on the decision to invade, we should all be dismayed regarding how the war was prosecuted. On the bright side, understanding such mistakes allows us to really appreciate how stunning the turn-around in Iraq is, and apply such lessons for future conflicts.