I don't think this game of saying that there was torture but we aren't going to prosecute anyone because they were just following orders is good enough.
If there was torture, go get some convictions. I don't want anyone thinking they can get away with this stuff. How long before we find out some 'crazy right wingers' have been waterboarded?
I think one of the reasons Obama won't pursue this is because it would upset the balance of power that the Democrats and Republicans have created. If one were to get serious about tracing orders and jailing those responsible, the Republican side of the power structure in D.C. would be seriously compromised. A range of possibilities would present themselves- a new party to fill the vacuum, a general uprising due to the perception that the people have no real voice, or a purging of the Republican party to the point where new republicans would have no allegiance to the status quo. Much better to keep the current crop around and have pointless little spats with people like Rush Limbaugh rather than do anything about torture, wipe out the current line-up of weak-spined Republicans, and then have to deal with the possibility of real competition.