This is democrats defending Obama, even if they would have attacked Bush for doing the same thing.
The cause is political laziness and the result is issue crossover.
Issue crossover is when you agree with Obama on one thing, and so you tend to give him the benefit of the doubt on other issues. This is only natural, but it can lead to bad policy.
It is like giving Hitler the benefit of the doubt on his policy towards invading his neighbors, because you like his progressive environmental policy (OK you idiots; I am not comparing Hitler to Obama. I am using a good logical debating technique of proving a point with an extreme case).
This means that democrats and republicans need to work with each other when they agree, because the other side has to be right some of the time, no matter how bad they are. And this also requires democrats and republicans to oppose people from their same party, because this will result in policy based on thought and logic, instead of whether or not you like the person in power.
Not being politically lazy means you have to think about each issue, instead of republicans who don't like Obama for one thing he did, crossing over that distaste for Obama's decision, to another issue.