Warning! Long rant ahead.
I'm getting more than a bit tired of people constantly making 99% negative generalisations on Arabs. While I'm in no way trying to belittle the problem of honor killings in Middle East, IMO somethig like this is always seen as a collective
tradition from the outside while similar deeds in our culture are always done by individuals
A research article I read a few years ago stated, and proved it's key points pretty well I think, that killing a wife or a girl friend is silently understood in the West too. The headlines most often potray the killer as a victim of uncontrollable feelings and shift the blame on the (usually sexually) misbehaving murdered woman, whose bad behavior forced the poor man to go nuts and kill her.
As an example: We have 1-3 yearly well publicized cases of a man shooting his wife and maybe kids and then himself in the event of divorce here in Finland. The headlines always scream "Desperation drove a man to commit extended suicide" rather than "Mother and kids brutally murdered by ex-husband". Some of the sharper journalists have recognized this as a form of honor killing, a way to make the humiliation of being ditched go away by destroying the humiliator.
Another interesting point made in the article was a reference to a Swedish study on men who were in prison because they had killed or battered their wives or girl friends. A psychologist interviewed these men and found that contrary to the common supposition, they hadn't acted in a frenzical blackout or under uncontrollable feelings. Most of the wife killers had committed their crime quite knowingly and believed it was their right as men to protect their honor by punishing a misbehaving spouse, eveng by death. They had did what they did, because deep down they believed in male superiority.
Note that previous paragraphs describe Sweden and Finland, two countries that are supposedly superior to the rest of the world when it comes to equality of sexes. Killing a woman endangering the honor of a man may not be publicly accepted in the West, but it still is subconscietiously condoned in our society too. Let the one without sin cast the first stone, ay?