Matthew Yglesias points out that the use of poisoned arrows is still against international law. Setting aside the issue of why present-day international law would be concerned with arrows -- surely we're not going to be refighting the Battle of Agincourt anytime soon -- I'm reminded of some disputes I used to have in college with my Dungeon Master when I was playing Advanced Dungeons and Dragons.
My DM insisted -- on what basis, I cannot recall -- that the use of poison, in any context whatsoever, is an inherently evil act and would therefore represent a de facto shift in alignment (the moral inclination of a player-character, for those unfamiliar with the game's terminology), with the requisite penalties in game play for an alignment change. I disagreed with this, positing a case wherein you're the local knight and your village is threatened by a magical dragon (as opposed to your everyday, non-magical dragons) which can only be killed via a certain poison. Is it an evil act to do so? My DM insisted that it was: if you are Good, you do not use poison. Ever.
I didn't agree, obviously, but I figured it wasn't a big enough deal to affect our gameplay.
My point? As ever, I don't have one. Heh!