Electric shock can be done without lasting damage. Not sure what lasting damage water torture does. Have yet to see the technique called anything but "water torture" or "Chinese water torture". Mock executions certainly do not cause "lasting damage" unless you include "emotional damage". Waterboarding actually can do lasting physical damage.
Some horrible crap is fundamentally different from other horrible crap. I still have the option of voting in the USA. If doing horrible things to people is one of the planks in his/her platform then I will vote against that candidate. Ivan the terrible may have boiled peoples skin off for amusement. The Romans crucified people. The inquisition ... I do not intend to vote for any of them either.
The CIA drone program looks a lot like terrorism to me. Some people like to argue that terrorism has a definition and the U.S. government is excluded from that definition. However, there are people who are living in fear of sudden nasty violence. It is a bad thing. I do not think the world would be a better place if we waterboarded government employees. I think ending their employment is a good step. Make them compete for minimum wage jobs in our suck economy. We could just remove the program funding.