The fact that the Islamic terrorist organization Hamas in its Gaza-based war against Israel is the aggressor and aims to destroy Israel and kill all Jews living there could not be clearer. Amid the mountains of evidence supporting this are the fact that Hamas’s founding covenant explicitly calls for the obliteration of Israel and the death of all Jews; the fact that Hamas has launched thousands of rockets from Gaza into Israel; the fact that Hamas has built a vast network of tunnels from Gaza into Israel for use in killing or abducting Israelis; the fact that Hamas produces and airs children’s television shows encouraging children to kill Jews; and the fact that Hamas regularly announces that it aims to “exterminate” all the Jews in Israel. There are many more supporting facts, but these few are sufficient to make the preliminary point.

The issue I’d like to address here is related and equally clear: Who is morally responsible for the deaths of innocents in Gaza, such as Gazan children, who are killed by Israeli bombs?

Obviously, when Hamas uses Gazan civilians as human shields—which Hamas admittedly and regularly does—and these civilians are killed, Hamas is morally responsible for their deaths. But suppose Israel bombs a Hamas weapons cache near which a child just happens to be playing and kills the child. Or suppose Israel mistakenly identifies a group of civilian teenagers as Hamas agents and kills them. Who is morally responsible for such deaths?

Hamas is. And this fact is clear to anyone who chooses to think beyond the frame of a television.

When the United States dropped atomic bombs on Hiroshima and Nagasaki, killing more than 200,000 people, the innocents in those cities were murdered by the Imperial Japanese who had attacked America and thus knowingly—premeditatedly—necessitated retaliatory force. Likewise, when Israel bombs Gaza in response to Hamas’s repeated attacks on Israel, any and all innocent Gazans killed in these bombings are murdered by Hamas.

In circumstances such as these, there is a clear-cut difference between the killer and the murderer. The murderer is the aggressor: the agent who initiates physical force and thus necessitates retaliatory force. In retaliating, the victim (or an agent on his behalf) might harm or kill innocent people in the process, but all such destruction is the moral responsibility of the aggressor.

The principle is: He who initiates physical force is morally responsible for the destructive consequences of the retaliatory force he thereby necessitates. So says the law of causality.

This principle is as clear in a war zone in the Middle East as it is on the streets of Miami. If a thug grabs a woman and tries to shove her into a van, and the woman pulls a gun from her purse and shoots at the thug, thereby killing an innocent bystander behind him, who is morally responsible for the bystander’s death? Every thinking adult knows the answer.

Of course, the kind and extent of retaliatory force warranted in a given situation depends on the full context and can be a complex matter. But the matter of who is morally responsible for the harm caused by retaliatory force necessitated by an aggressor is simple: The aggressor is.

Hamas is morally responsible for all the deaths and all the destruction resulting from the retaliatory force necessitated by Hamas’s assaults on Israel. Hamas and Western leftists pretend not to know this. Never let their pretense go unacknowledged or unannounced.

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