Let's state the obvious–killing of any kind is a regrettable, horrific act. But, as in all actions, there are degrees of karmic consequences. Killing someone in self-defense is not the same as premeditated murder. Accidental killing is not the karmic equivalent of planned, dispassionate slaughter.
Is there a moral equivalency to the liquidation of innocent Jewish children in Toulouse France and the accidental death of Palestinian children during Israeli retaliation for rocket attacks? Mohammed Merah apparently thought so. I think not.
Karma is powerfully derived from the notions of motivation and intention. Kavanah is the Kabbalistic term for intention.
When noncombatant / civilian deaths occur during military action there should be a response of regret and revulsion. They were clearly not the intended target.
When Israeli (or American military actions) result in the death of civilians (adult or children) there is an immediate reaction–regret and condolences for the unintended deaths. When soldiers deviate from accepted standards of military conduct (as in recent killing of Afghan civilians) there is immediate and harsh response from the American military itself. It is what civilized people and nations do when accidental killing occurs or when rogue individuals transgress.
When innocent Jewish civilians are deliberately slaughtered by Islamic fundamentalists, there is no offer of regret. In fact Mohammad Merah's only regret was that he could not have killed (and video taped) more.
The notion that the purposeful, intentional murder of innocent human beings will bring heavenly reward is the most, obscene, perverted notion of spirituality that is imaginable. Even Hitler never made such an assumption for his actions.
Perhaps this represents the clash of cultures. But what does that really mean? I'm afraid it is quite clear. Barbaric, inexcusable actions need no explanation. And by the way, did I miss the news of world wide Muslim condemnation for this horrific act? Any religion which makes excuses for such actions needs serious self-examination if it is to claim spiritual validity.
Hell has a special place for such murderers. But if hell doesn't exist, karma will take care of it.
At the very least the life review every soul experiences after death is the perfect justice. Every experience, every act we have committed and its impact on other souls is experienced and felt through the eyes and mind of the victim.
Hope Merah is enjoying his.