That bacon bap earlier this month was not the cause of Ed Miliband’s unpopularity. Ed Miliband’s unpopularity was the cause of the bacon bap. Scant comfort this will give the Labour leader and his fabled ‘advisers’, but they can stop worrying about food-related photographic gaffes because once the world is out to get you, the world will get you, and if they don’t get you one way they’ll get you another. Sooner or later Mr Miliband will have to eat, and sooner or later a shutter will click as he opens his mouth.

In peacetime politics, most attack is the consequence not of an opening for attack, but of a desire to attack. Intelligent commentary does not dwell on the opportunity but asks the reasons for the desire.

I pick up my newspaper and read: ‘Nick Clegg is “toxic” on the doorstep, a Lib Dem peer told the BBC’s Sunday Politics.’ No. The Liberal Democrat party is toxic on the doorstep and Nick Clegg is the leader of the Liberal Democrat party. Do you honestly think that— oh, Ed Davey, say, or Simon Hughes or Tim Farron — would now be the flavour of the decade if for the past four years they had led their party in an alliance with its former foes and broken their election promises as a result?

Ed Davey we’d be calling ‘Ed Who?’ and describing as the ultimate flavourless bore, photographing him in the dreariest poses we could find. Simon Hughes would only have to mount a bicycle to be captioned as a hapless young curate calling in for tea. And woe betide Tim Farron should he ever draw a raffle and grin: we’d chortle that the lightweight young hopeful was auditioning to be a presenter’s sidekick on a regional daytime TV gameshow. I remember when Tony Blair as Prime Minister scuttled out of the Commons chamber in order to avoid listening to a junior minister resigning on principle. Because he was riding high at the time this was seen as displaying lofty disregard; had he been unpopular we’d have called him chicken.

Mr Clegg is only the scapegoat for the anger of supporters of a party of fuzzy protest because now their party has been obliged to focus. An ill-considered portrait of Miliband with his mouth open was nothing more than the entry point for national scorn for a Principal Opposition that can find no attractive alternative to an unpopular government’s policies. A party leader becomes its symbol. Like the tip of a magnet, that is where the iron filings will fly when things go wrong. But look to the whole magnet for its power. Replacing the tip might make less difference than you think.

Hundreds of goofy pictures of people in the news are being taken all the time, for use as or when desired. Ed’s brother David suffered mauling-by-banana — at a point when he was dithering. David Cameron was unwise enough to try to change on the beach while screening himself with a towel — but who hasn’t? Neil Kinnock was criticised for falling over on the beach at Brighton. Michael Foot was lambasted for wearing a duffel coat at the Cenotaph. All these photo-inopportunites were doubtless embarrassing, but the world only picked up on them, and the media only ran with them, because we were looking for ways to sneer at the individual. Ed Miliband may have tackled a small piece of dead pig, but Margaret Thatcher lifted an entire live calf at a farmer’s market once, as the cameras snapped. True, we smiled at the unwisdom: but people thought the Tory leader rather game and the unwisdom a matter for amusement rather than contempt.

Boris Johnson could eat a bacon bap tomorrow — and turn it to his advantage. Remember when his zip-line ride came to a stop in mid-air, leaving the Mayor of London swinging? Mr Johnson could wave a banana and be chuckled at for advertising his masculinity; and if he fell on the beach we’d suspect he did it on purpose. Nigel Farage can place a pint of beer on his head, and the captions call it an act of triumph rather than folly.

So it’s cheap of enemies and lazy of commentators to fall into a chorus of giggling censure at one infelicitous snapshot of Miliband. Speaking as one of the gigglers I’d hazard the suggestion that among the reasons for a tendency to mock is the uncomfortable knowledge that, though we keep recommending the Labour leader find a tune the electorate and its news media can whistle, we can’t actually think of one. Our country’s economic circumstances these past four years have severely constrained ambitious policy thinking; it isn’t even clear that realistic politics in which voters could believe offers space anywhere much to the left of the present coalition government.

When Miliband seemed to be proposing nothing significant we mocked him for vacuity. When he announced some rather left-wing ideas we complained they were left-wing and anyway lacked a unifying theme. The unifying theme is implicit: it would be a rousing defence of the benefits of muscular state intervention. Were Miliband to make that explicit we’d say he had ‘broken cover and come out as an old-fashioned socialist’. Were he to say he was sorry for his party’s spendthrift past we’d crow that he was eating humble pie.

So he says nothing and eats a bacon bap. Just tell me without hesitation or deviation what a Labour leader could do or say that the British media could get behind?

Mr Miliband does have a problem, but it is entirely unrelated to his choice of snack, and it’s our problem too. It is this: nobody can think of a principled position that a left-of-centre party could adopt and that the voters could believe in. So we drive a Labour leader into the corner, then call him goofy.

Sooner or later, Ed Miliband will be caught striking a fine and flattering pose in dignified circumstances which everyone can applaud. And believe me: we won’t use the picture.