By now it should be clear to practically anyone who follows news with even the mildest critical gaze that the leaders of governments lie. In order to serve their purposes, they are willing to lie routinely, unscrupulously, shamelessly, and indiscriminately. The only thing that stops them from lying is the fear of getting caught and even then, in the case of James Clapper who still has his job even after lying under oath, it is sometimes not enough to stop them.
This is why journalists should never, ever, accept the word of government officials without asking for evidence. And yet this BBC journalist is shocked, just shocked, that Greenwald is accusing the intelligence chiefs of the UK and US of lying. Of course, journalists who are careerists know which side their bread is buttered and love to curry favor with the big shots in government and this explains their seeming naivete.
What I like about Greenwald is that he has no hesitation to blasting such pseudo-journalists while never raising his voice, merely using his seemingly encyclopedic recall of history and facts. He reminds me very much of Noam Chomsky in this regard. What he does to this journalist is a joy to behold.