Mr Key summoned up a hypothetical question for him: what would he say, as one who had called for limitations on government spying, to the family of somebody killed by a terrorist?
Refusing to be flummoxed, Mr Beagle pointed out this was "a meaningless question", the logical extension of which was we should leave no liberty unbreached in the effort to forestall the suffering of this imagined family. Cameras in everyone's houses? Torture? Whatever it takes.
Mr Beagle, like Mr Dotcom, and everyone else, had only a few minutes before the committee. But even that sampler menu was enough to underline how useful, how democratically healthy, it would be to hold a wider review into New Zealand's security services.
John Key deserves praise for taking the time to chair the sessions, even if he tried the patience of some with the sullen indifference on day one and the cod-naivety on day two. (At least, I hope he was playing it cute in pretending not to know anything about encryption; the alternative doesn't bear thinking about.)
And Mr Key is just the man to navigate us all through a proper, broader conversation about the kind of sensibly calibrated surveillance agencies we need. It could all be done and dusted in a couple of months. The sprint, however, in pushing the GCSB bill and associated telecommunications intercept legislation through the parliamentary process under urgency, is unnecessary and wrong.
David Shearer awkwardly attempted to thank Mr Dotcom for bringing everyone together. And it's certainly true that the faintly dream-like rendezvous - Mr Dotcom, Mr Key, Mr Shearer, Russel Norman, John Banks and Peter Dunne all gathered before an eager circus crowd - would never have happened had the GCSB not been caught out doing illegal snooping by the high-powered legal team enlisted by a flamboyant, Coatesville-based German emigre with a dogmatic US state prosecutor in pursuit.
At times it's hard to fathom the impact that Mr Dotcom's decision to settle in New Zealand has had on our politics. Without it we'd not have seen, of course, the gung-ho raid on his mansion. Mr Banks would not be in court facing a private prosecution of donations to his mayoral campaign.
The Prime Minister would not have had to waste all that time so conscientiously not reading the police report about those donations. Nor would he have faced all those uncomfortable questions about calling up a friend from school days to head up the GCSB. Peter Dunne would still be a proud minister of the crown. "Brainfade" would not have become one of the most commonplace nouns in our political lexicon.
But for all the material dispatched from the great Dotcom scandal centrifuge, John Key sails on, serene, relaxed. Polling at a gobsmacking 60-something in the preferred prime minister stakes, in large part thanks to the opposition's clumsy shadow-boxing, he looks just about unsinkable.
Unless, of course, Mr Dotcom can produce the evidence that he promises proves that the Prime Minister, contrary to repeated assurances, knew all about him before last January's big raid.
But, he says, that scene won't play until his extradition hearing. And that's a day we may never see.
In the meantime, it all looks rather like a mega-bluff. See you later, whistles the Prime Minister. It's been fun. Sadly, I doubt we'll see them in the same room again.
