Your comment is in reply to a comment about China, which is why I referenced China. (But if you wish to say your point is abstract, then my comment also applies equally well in any direction - I don't think China should use the US's misdeeds, which are plentiful, as justification for their misdeeds either!)

I am unconvinced that abandoning the attempt to be the good guys will lead people to be good. I believe it will only allow people to be bad guys without feeling bad about it. While claims to be moral have of course been used by many bad guys through history, the correct response is to argue convincingly that they're immoral, not to give up the idea that morality is a worthwhile standard.

Or, in other words, I believe morality is qualitatively different from any of those other categories you list. If a store chooses to sell Chips Ahoy instead of Oreos, that's just a question of taste; if a store chooses to sell cookies filled with razor blades and arsenic instead of Oreos, that's a different matter entirely, and we are not obligated to accept it because we've accepted that stores can sell Chips Ahoy.