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This might belong in pre 1900, since IMO you can't get a Communist/Socialist America without a POD before 1900, and even then it looks more like a muscular French Popular Front than the Soviet Union, but...

Would America change its flag in the event of a Communist or Socialist victory? Red flags everywhere, sure, but it seems like the American flag is fundamentally different than the Union Jack, or the White Red and Black of Germany. Even East Germany kept the black red and gold, and just added to it.
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