Actually, Kagan is replacing Stevens, not Breyer. It doesn’t represent a shift. Like Souter before him, Stevens was a disappointment to the Republican president who appointed him.
K, thanks ... wasn’t able to follow it that closely. So the court hasn’t shifted which is good.
Souter and Breyer turned out to be more left than anticipated. I think it’s a given that Kagan will be more left than she portrayed herself to be or than Republican senators who voted for her convinced themselves she is. She may be a leftist replacing a leftist, but I’m convinced she is more left than the justice she is replacing. I hope this qualitative difference may not harm the country in a material way.