I think you are conflating several diffrent kinds of "conservatives" here.
First, I wouldn't call George W. Bush a failure
Thousands dead in a war of choice is the ULTIMATE failure for a President; he also refused to fund SELA requests for the ongoing NOLA levee restoration. We will never know if the levees would have failed had the work been on schedule. One of the WORST in US history. And, he took the heat OFF al Qaeda to send US troops to a war in Iraq deemed ILL PLANNED by the JCS.
Obama has not done great in office but anyone compared to baby Bush looks good, except for for Buchanan and Pierce.
George Bush has been the closest Republican have got to their extreme ideal. He was a "perfected" Republican.
Really?
Frankly, I've never understood why the Democrats hated Bush as much as they did. He made government bigger, he created new entitlements, he peddled himself as a "Compassionate" conservative who opposed the more draconian cuts that Gingrich did. He let Ted Kennedy design "No Child Left Behind." Yeah, he went to war with Iraq, but he made sure he got Democrats on board before he did it.
Didn't matter. You guys hated him because they hated Clinton. And they hate Obama because you all hated Bush. And whoever follows Obama (it hopefully won't be Romney) you guys will turn around and hate some more.
Where does it end?