There is a very, very easy answer to that. When Reagan first nominated O'Connor, we are all not as well-tuned to tendency of judges to move left. In addition, it was not as clear to all of us that the left was fighting its culture war through the courts.
It is for this reason that Reagan didn't campaign on judges in 1980, or 1984. It wasn't considered as big of an issue then.
Since then, we have had Souter, and we have had the liberals attack every single institution that we cherish through the courts.
As a result, judicial nominations are front and center for us, and they were a major rallying cry for why we should all support Bush.
So, do you understand now?
Excellent!