A lot of presidents receive this sort of treatment, so this is not a new phenomena in the least.
A lot of US presidents have had their birthplace publicly criticized, as well as their faith, and have been accused of being a terrorist? I used to be into presidential trivia as a teenager, and I can confidently say you are wrong in the assertion this treatment happened to "a lot" of past presidents.
Whether you feel comfortable agreeing this is at least partially racially motivated is your prerogative, but don't twist facts.
And, again, it is a huge jump in logic. You cannot possibly have enough information about all of the people who want to see a certificate to accurately label them as a racist or not.
To clarify for you, I feel the aforementioned criticism has some racial motivation. This is different than labeling everyone who wants to see his birth certificate racist, which I have not done.