I gave Obama a 50-50 chance at getting murked his first term in office. I think the chances have gone up second term since he got reelected. He needs all the protection he can get himself. And is justified extending it to his family.
For all we know Craig Robinson the Oregon St coach has a body guard because he's Michelle's brother.
If Obama doesn't get assasinated after 8 years in office he deserves a lot of credit for it. Not getting yourself killed is a big part of being president. 2 of our best presidents ever fucked up in that regard.