I think it’s reasonable to assume that Kennedy knows his own mind perfectly well. He’s not pulling these decisions out of the ether any more than his colleagues. The Republican Party of the 1980s was simply a much more ideologically diverse coalition than the Republican Party of 2010. This was especially true on certain kinds of social and cultural issues. Ronald Reagan was a popular political leader in New Jersey, not just Alabama. In the modern day, Kennedy’s particular mix of viewpoints has become rare, but that’s just a sign of how much things can change over the course of a 22-year (and counting!) spell on the Supreme Court, not a sign that he’s somehow confused or particular easy to persuade.