War is not a balancing act. To give your enemy a right to say what is right or wrong with your behavior is to give them another weapon. If you are fighting “fair” you have already lost the fight. Admit who is your enemy. Pick your targets and be willing to take the steps necessary to act against them with all means available. Or loose and talk about the great game you played while they trounce you into the ground.
I hate the necessity, but I fall on this side of the discussion.
I think back to one of the films in WWII with the same discussion. The conclusion was that if you take the ethical position that you would rather loose the battle than use NAZI tactics, you will be conquered by them. "Rules for Radicals" by Saul Alinsky is proof that we must match or surpass them at their game.
Having said that, using false data that are easily proven to be lies is also self-defeating.