There is nothing hard to understand about this at all. There were then, and there are now, four hard-core "conservative" (actually, crypto-fascist) judges on the Supreme Court - - Scalia, Thomas, Alito and Roberts today, Thomas, Rehnquist and two others in 2000. There was a swing voter, Kennedy, who sometimes sided with the "conservatives" and sometimes with the liberals. Kennedy is still on the bench and still serves as a swing voter. Sandra Day O'Connor, no longer on the bench today, was a sometime swing voter who could have linked up with the four crypto-fascists to produce the result they wanted.
The concept is not yet a solid wall of crypto-fascist judges, but the attempts of the Reagan and Bush administrations to build the wall one brick at a time. Currently with four bricks. Another Republican President, and it is a certainty that as liberals retire, crypto-fascists will replace them. At this point, the Republican dream has yet to be realized, ans swing voters and liberals can combine to block crypto-fascist attempts ot promote torture and deprive prisoners of their rights to a fair trial.