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In America, "Harlem Shake" may be the top pop single. In Egypt and Tunisia, there's some serious Harlem shaking going on. And it's causing leaders to tremble as it becomes a potent symbol of protest, revolt and defiance.

Take the kids in the video at a school in Tunisia. They danced en masse to the song and posted their exploits on YouTube. That prompted a quarter of a million hits and reports of an investigation by the country's minister of education and that prompted a backlash. Video after video after video of Tunisians proudly doing the Harlem shake in defiance.

More from CNN: What the Shake has to do with Harlem

And then there's Egypt, where the authorities went further and the backlash was worse. Four pharmaceutical students were arrested for doing this Harlem shake in front of the pyramids, and that set off a big reaction. Late in the week in Cairo, there was a mass shake in front of the Muslim Brotherhood headquarters to protest.

Now, who says America's popular culture exports have no value?