John Stewart — not that Jon Stewart, the one with the H — was voted the U.K.'s most effective environmentalist in 2008. Like our Jon Stewart, he gets things done. So how come his visa was revoked while he was over the Atlantic, traveling to the U.S. for a speaking tour?

Stewart was invited to this side of the pond by a coalition of environmental organizations, who had planned for him to speak in six cities across the country. Instead, he was detained for six hours at JFK Airport, then put on a plane back to London. What the hell?

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Well, it's not totally clear what the hell. Stewart says immigration officials expressed concern that he planned to discuss "the role that peaceful, non-violent civil disobedience played" in a campaign he helped organize. But if discussing the role of civil disobedience is really a strong enough rationale for revoking someone's visa mid-flight, then a) something is maybe pretty wrong with our immigration laws and b) how are 20th-century historians ever allowed to travel? 

The speaking tour is going ahead by teleconference, even though Stewart and the other speaker, Dan Glass, were both prevented from entering the U.S. (Glass didn't make it as far as an airplane, because he never received a visa — his was hung up in "administrative processing.") Here's the irony: Stewart and Glass are speaking about their campaign against the environmental impacts of aviation. 

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