User blog comment:Callofduty4/Why is it a sin for Treyarch to rip some aspects off of Infinity Ward but OK for Infinity Ward to rip off some stuff from Treyarch?/@comment-1721748-20091225083030

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The reason CoD:4 sold so well is because it had a intricate storyline.

That's because it's fiction.

You can't fictionize WWII.