Fascinating case in point : Was Miranda carrying information from Poitras to Greenwald? Given that any electronic communication between the two would be eagerly examined by "interested parties", it's plausible. It would be astonishingly naïve of them, but that's not implausible.

Visibly he was detained because he was on a watch list :
Glenn Greenwald's partner detained at Heathrow - reaction | Politics | theguardian.com

* The US was given a "heads up" before David Miranda, partner of the Guardian journalist Glenn Greenwald, was detained in London. White House deputy press secretary Josh Earnest confirmed on Monday that the UK alerted the US government that they would hold Miranda before he arrived at London's Heathrow airport.

* The White House said it did not give the order for Miranda to be detained, but nevertheless was kept aware of developments. "We had an indication it was likely to occur but it's not something we requested," Earnest said. Pressed on when the US was told Miranda would be held, he added: "It probably wouldn't be a heads up if they had told us about it after the detainment." Earnest said it would be "accurate" to interpret this to mean the US was told Miranda would be detained when his name appeared on the manifest.

* Earnest would not deny that the US had obtained access to Miranda's electronic material. Several items, including laptops, were seized at Heathrow. Asked by a reporter to "rule out that the US has obtained this material", Earnest said: "I'm not in a position to do that right now."

NUJ - "Shocking detention" of Miranda part of abuse of anti-terrorism law

"Miranda had been used as a go-between by Greenwald and film-maker Laura Poitras, in Berlin, who had been working with him on the information supplied by Edward Snowden. This material has now been confiscated. Journalists no longer feel safe exchanging even encrypted messages by email and now it seems they are not safe when they resort to face-to-face meetings.

 

"This is not an isolated problem. The NUJ believes that journalists are coming under more scrutiny and surveillance, being stopped at borders and their work interfered with, simply for doing their job. We are currently collating examples of such unacceptable interference across our membership. The treatment meted out to David Miranda is wholly unacceptable and it is time the use, or rather misuse, of terrorism legislation as a way of targeting individuals was properly and independently reviewed."

_{It is rightly acknowledged that people of faith have no monopoly of virtue - Queen Elizabeth II}