He also was a constitutional law professor at Chicago University. The same law school Antonin Scalia graduated from. As a graduate of Harvard Law School I have to believe he knows the Constitution. Whether he'll adhere to it is another matter but at least he might be compelled to give the Constitutional reasoning behind his policies. McCain probably thinks our constitution is what allows him to have a decent bowel movement in the morning.
I think it was Twain who said "it's not what people don't know that make them ignorant it's what they know that ain't so."