Its just how we look at things in the past, I think, that lead us to "assign blame/give praise" to presidents who break or fix the economy. I agree that in many cases, its not a president's fault that the economy goes in the toilet. The Great Depression and the Housing Crisis wasn't exactly caused by presidential action, though conditions didn't get any better (or got much worse, IMO, in Bush's case) under some of those presidents. However, there is a reason that the party in charge will get the credit when the economy turns around, because they have to make some kind of policy to get us back on track. FDR's praise is well-deserved, for instance, because he actually did stuff to help us out (and having a world war didn't hurt either), while the three presidents before him just couldn't get out of their little funk, so to speak. So we put blame on Bush Jr. and Obama because they haven't gotten us out. We praise Clinton because he helped get us out of the last one.