CIA's airstrike on Al-Zawahiri

Reading at cnn about the Airstrike, I am seeing alot of alarming quotes that are really getting at me. I understand sacrifices must be made to defend the USA, but why are so many innocent being killed to do so?

Friday morning's strike killed eight men, five women and five children, Pakistani intelligence sources told CNN. Three homes were targeted.

Three months after the 9/11 attacks, U.S. forces attacked al-Zawahiri's residence in Afghanistan, killing his wife and children.

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If an airstrike happened on US soil and innocent kids were massacred, we would be looking at a world war. Why is it ok for these guys though?