Why didn't he buy an American car like the Volt?
Because Nissan has a car plant in his state of Tennessee which is scheduled to start producing Leafs of its own in 2012. I don't think Alexander is worrying about running for president again, and was thinking more about supporting a business that employs Tennessee voters.
And because when it comes to buying cars most people think about more than petty nationalism.
Because its so awesome when american companies go out of business? what does Obama drive, a lexus or mercedes?
It's not awesome when companies go out of business, however I shed no tear for their failure to perform at a level to satisfy the American customer.
And neither do I group car companies collectively by national origin. I myself own a Ford (yes an American car) Focus 2007 SE and am satisfied by how it has performed to my standards. I previously owned a Saturn SC2 2001 (another American car) that I thought was very good (it got 45 mph on highway). Attempting to link me to anti-American car company hacks will fail.
My point is that the average American customer thinks about what automobile to buy that gives them the best value and efficiency, not feel good mentality on whether or not the company they buy from is Murican. I know people who drive Hondas and Toyotas and it doesn't cause me to lose sleep at night.
The fact that you are offended that a random American politician would buy an automobile that best suited his needs speaks more about your own biases against the global trade environment than it does about any "glee" I might have about American companies failing (which I most certainly don't).
Don't worry though, you are not alone: