News International's problem is now Cameron's problem.

Employing and then losing Andy Coulson illustrates the Prime Minister's worst flaws.

You're in favour of abolishing the monarchy and have probably done it more damage than anyone since Cromwell. You despise the class-ridden nature of contemporary Britain. And you played a central role in Labour's three crushing general election victories, supporting the party in every poll between 1997 and 2005. But still the left hates you. So who can you be? None other than Rupert Murdoch, who's in a bit of trouble. Not his fault, of course – how was he supposed to know what his bestselling newspaper was getting up to during that brief period when one rogue individual was getting up to whatever it was? Why on earth would Rupert have paid attention to that, then or since?

No, all this has obviously come as a vast shock and has, right now, right in the middle of this pesky Sky bid referral business, just this moment come as a shock to Murdoch. But while there is absolutely no possibility that the owner of the News of the World is in any way personally culpable for what his paper did; David Cameron can't escape responsibility for his sins of commission in quite the same way. For employing and then losing Andy Coulson illustrates all the Prime Minister's worst flaws and promises plenty more harm to come.

The first thing that needs to be said about the phone-hacking scandal is that the internet has had nothing to do with it. This has been a story that has been kept alive by antique media, being almost entirely the work of the Guardian and the BBC. (Though perhaps that gladdens Rupert's romantic heart?) It's hard for Tories like me who fall into the "shut it down" rather than the "sell it off" camp, as far as the BBC's concerned, to face up to what it would have meant if the corporation hadn't existed. Fleet Street is so compromised by its own relationship with the police, past and present, that it hasn't been willing to give any heft to this story, if it can avoid doing so. It took the BBC to make this story -- and all those Tory flacks who screamed that there wasn't one here are discreditable fools. But for all that Murdoch is the real story, it's the Andy Coulson chapter that tells us a depressingly large amount about the Tory party that Cameron leads.

Even in the manner of his departure, Coulson reminded us, and more pointedly, the Prime Minister, what sort of man he is: "I've kept a diary!" being one of the century's most unsubtle threats thus far. When Cameron made him his spin doctor, immediately in the wake of the first elements of the News of the World scandal emerging, plenty of Tories shook their head.

Cynics wondered about the practicality of the second chance being offered, and whether it would end in tears, while traditionalists simply wondered what the leader of the Tory party was doing giving hundreds of thousands of pounds to man who ran front page after front page attacking and undermining the royal family. However modern the party was, it surely didn't need to be quite that modern? But how those monarchy-knocking stories came to be on Coulson's front page has come back to bite Coulson and Cameron good and hard.

One of the problems with the left is that, at root, you just don't respect the right: you think we're absurd, unreasonable, dishonest, or merely dim. Thus if you read that pro-monarchical sentiment motivated some of the people who were right when David Cameron was so very wrong, you either don't believe it, or you laugh it off as being risible. Yet, it was taking on the monarchy that was the step too far even for News International.

Hacking into the phones of royalty obliged an intimidated Met to act and that's what has set in train the greatest challenge Murdoch's empire has ever faced in Britain. It's certainly getting a far harder time than it ever got during any of those three parliaments, with their massive Labour majorities, for which Rupert had his papers campaign. You really might want to consider standing up for "God Save the Queen" the next time you hear it, as the press regime isn't anywhere as nice.

Who can blame the police for their reticence? When they arrested Damian Green for being in receipt of the contents of ministerial safes, because one lone civil servant felt he knew best where those contents should be, who stood up for them then? Partisan, Cameron-cheerleading Tories frothed at the mouth and disgraced themselves by calling the police "Nazis". And the liberal left wasn't exactly vocal in its defence of John Yates et al, either.

Having been burned by that experience, and after the frustrations of having to accept that no crime had been committed under the inadequate laws that provided for the cash-for-honours investigation, who exactly were the Met to look at for help in taking on any element of our sacred free press? Labour? Even today Ed Miliband can't wait to assure Rupert that he'll come running, should he ever be called.

Labour's ongoing fear of Murdoch was amply demonstrated by PMQs this week. Only the heroic Tom Watson stood up and asked a question about the phone-hacking scandal. The leader of the opposition certainly didn't feel the need to waste any of his questions asking, oh, "Did the Prime Minister discuss News International or any of its subsidiaries when he secretly met James Murdoch and Rebekah Brooks in the immediate wake of Cablegate?" Even though, thanks to the Independent, we know that Cameron's I've-always-got-away-with-it arrogance is so colossal that he willingly ran the risk of his conclave emerging last year, in the heat of Cablegate.

There's a school of thought, exemplified by the Telegraph's Charles Moore, that says that Cameron is an admirably cold-blooded, sure-footed master of business. In short, a grown-up who knows how things are done. If only. Anyone whose judgement is so poor that they go to a meeting like this merely confirms everything that went into his mistake in appointing Coulson in the first place.

The new Tory comfort-blog about Cameron's serial incompetence is that, with Coulson gone, the story goes away as a problem for the Prime Minister. But it's the opposite that's true: precisely because Cameron needlessly drew Coulson into his inner circle, every subsequent eruption from News International is now going to rain down on No 10, too. And if last week shows nothing else, there's plenty more hot stuff to come.