Do people understand how water-boarding is used?

What I understand is that after World War Two we prosecuted water-boarding as a war crime. During Viet Nam we court martial led American military who used water-boarding. And now, because we are a bunch of scared little children, we want to run around using a discredited technique which we previously defined as a criminal act. That makes us hypocrites at best and the debate over its efficacy is meaningless..