I was accused of the logical fallacy of ‘Moral Equivalence’ more times than I remember on another blog, so I did some research on the subject.
Moral Equivalence is indeed a type of logical fallacy – many people use the term in different ways but it could be summarised as George Orwell did as “the argument that half a loaf is no different from no bread at all”. That is treating two things that are different in quantity but the same in quality as being exactly the same.
An example of such a logical fallacy is the argument that America is the same as (or as bad as) a totalitarian state. There are some features of the American ‘managed democracy’ that could be compared to totalitarian regimes, however it is not a totalitarian state.
However there are times when it is a useful technique to compare our own behaviours, practices and morals with those of our enemies and ask whether in some way we ourselves are just as bad as them. It is also valid for others to point out inconsistencies and hypocrisies in our arguments by saying that we do the very same things for which we criticise others. One way these arguments are deflected is to label them with the tag “Moral Equivalence” thereby implying that they are necessarily fallacious.
Whether an argument resting on a comparison of our own conduct with those we are criticising is valid or not is a matter of judgement on the part of the participants. It can be just as much a poor technique to label an argument automatically as “moral equivalence” as it can be to stretch some comparison to make a point.