“[He] that do bring the news made not the match,” wrote Britain’s most celebrated playwright; that country’s government should perhaps learn his lines. On Sunday, the police at Heathrow detained David Miranda — the partner of lawyer-journalist Glenn Greenwald who brought Edward Snowden’s leaks of U.S. National Security Agency (NSA) documents to light — for nine hours, interrogating him under the Terrorism Act. Mr. Miranda, a Brazilian, was returning home from Berlin, where he had been in touch with a film-maker working on the Snowden files. If the Cameron government took aim at the messenger, it has shot itself in the foot. The episode reveals an establishment desperate to please its “special” ally, the U.S., and cover up its own egregious surveillance operations. That Mr. Miranda’s airport detention was meticulously orchestrated indicates it had the blessings of elected officials at the highest level — the White House’s acknowledgment, that it was given “a heads-up” in advance, confirms as much. This is not the first time innocent individuals have been targeted for their alleged role in the NSA leaks. Last month, four European nations closed their airspace to Bolivian President Evo Morales, on the unfounded claim he was ferrying Mr. Snowden to safety. Attempts to intimidate David Miranda, and through him, Mr. Greenwald, represent a new low: the “liberal democracies” in question seem capable of plumbing any depth to mask their surveillance schemes.

Edward Snowden may have been granted temporary asylum in Russia, but the West has taken upon itself to plug any further leaks by harassing journalists. Alan Rusbridger, The Guardian’s editor, has narrated how officials threatened him for months to surrender or destroy the material his newspaper obtained from Mr. Snowden. The British government then used the threat of legal injunction to ensure the physical destruction of Guardian computers purportedly containing sensitive material. If Mr. Miranda’s ordeal exposes the readiness of governments to twist the implementation of draconian laws out of context, the threats Mr. Rusbridger has written about highlight the scant regard the British government has for its own press. Mired in their efforts to “control the damage” caused by Mr. Snowden’s leaks, the U.S. and its allies seem to have lost the plot. The NSA documents, in the publication of which Mr. Greenwald and The Guardian merely served as conduits, have triggered a robust public debate over where intelligence agencies should draw the line in their snooping. Instead of swiping blindly at those standing up for privacy, the U.S. and Britain should learn to respect within their own borders the freedoms they supposedly champion around the world.

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