I think you underestimate Europeans and their grasp of international politics. I wouldn't be surprised if Europeans know more about Obama that most Americans do. I think Obama embraces a lot of the political ideas he sees around the world, so a lot of foreigners understand his policies better than most Americans do, having experienced the benefits of their impact.
I honestly also do not know how Obama can mess up the USA more than it has been messed up in the last 8 years. To go from a nation that most people admired, to one most nations mock shows just how much impact one man can have on a whole society.
When all American tourists start saying they are from Canada, then you know something is going wrong. So just the fact that most American tourist no longer deny being from the states means Obama must be doing something right.