my definition includes, but isn't limited to, valor in battle
sometimes honor may be not going to war, which is sometimes the more appropriate choice.
honor and nationalism have definitely been "misused" in the past (nazis is a case i think would all agree on), but then that would depend on your point of view. perhaps you could only view it as "misused" in that the problem was at the top (hitler and his party), and that the concepts of honor and nationalism are impossible to misuse. it seems to me if you drape it in a flag, honor takes on the subjective baggage you associate with that nation. is it possible to view valor outside of the baggage? i'm sure some people can appreciate the code and valor of a kamikaze pilot, but i'm sure those on the carriers that were their target had a different point of view.
i don't think honor is a bad thing, it is certainly a noble aspiration, but it is also useful to see the same trait in the enemy and recognize that it is not something we have a patent on (other than the honor the represented by the American flag)