Because, a Roberts for O'Conner was a significant shift to the right for the court and the Dems failed to stop it. By making it a Roberts for Rehnquist, it is a neutral move. It may not like seem significant, but wait for the spin to begin. It will be a huge defeat in the area of spin. Bush could have picked a 2nd Conservative Justice with solid conservative credentials and sold it as a Rehnquist replacement. Bush lost that luxery and is now in for a huge fight on his next nomination. Dumb move, IMHO.
Exactly my point above. The response above was that he will cover that base by choosing a woman. I'm not convinced but I'm usually wrong anyway.
I still don't see it that way. Granted, the dems can't manage to damage or stop the Roberts nomination regardless of who he is replacing. The inevitable "fight" was and is going to take place on the 2nd nomination anyway, so it doesn't really matter.