Okay, there’s something that’s bugging me today. By even mentioning it I’m sticking my head on the block very slightly, and I’m sure the social media response to this post is going to be a treat. But I’m going to say it anyway, because it’s really, really winding me up:

Yes, there is a very good reason the tube strike is national news today. And no, it isn’t comparable to a problem with the buses in Huddersfield.

The idea that the strike is just a little local difficulty is a superficially truth-y one. London, after all, is just one city, where the vast majority of the country do not, in fact, live. What’s more, as the political, business and cultural capital of our ludicrously over-centralised state, unnecessary attention paid to London is likely to annoy people in the way a sudden focus on, say, Bradford probably won’t.

What’s more, by any reasonable definition, the British media is too London-centric. It’s an unfortunate but inevitable side-effect of the fact that most of us live here, and CityMetric is very definitely not immune to this problem. (I’m always keen to correct this where possible, so if you happen to be in charge of another British city and would like me to come up and see you, do get in touch.)

Nonetheless, it’s entirely reasonable that the tube strike should be leading today’s national news, for at least two reasons.

One is that London is not just another city. It isn’t simply that all the journalists and politicians live here (though, that no doubt helps, when it comes to garnering coverage). It’s that a whole lot of other people do.

Exactly how many is quite hard to say, because the city has been growing pretty fast, but it can’t be far off 9m by now – roughly one in seven of the national population. If you consider the entire metropolitan area, which includes the commuter belt – as good a proxy for the number of people affected, directly or indirectly, by the tube strike as we’re likely to get – it’s closer to 14m.

I sort of suspect that any other political issue that affected 1 in 5 of the British population would be leading the news today, too.

Population estimates for 30 June 2015.

It’s easy to forget quite how big London is: because it’s just a city there’s a tendency to assume it’s on a level with other British cities. But it isn’t: it’s at least three times bigger than any of its rivals, and at least 40 times bigger than Huddersfield. It’s probably slightly bigger than Scotland and Wales combined, too – on which measure, Sadiq Khan is a significantly more important politician than Nicola Sturgeon.

The other reason why the tube strike is a national matter is related to this, but exacerbated by our old friend, the north-south divide: London represents a disproportionately big share of the national GDP. Estimates vary, but tend to be somewhere between 17 and 22 percent.

In other words, every fifth pound that the British economy is meant to be generating today may never materialise because people couldn’t get onto the Piccadilly line this morning.

None of this means the media isn’t too London-centric: it definitely is. Nor does it mean that it’s ludicrous the economy is so dependent on one giant city: that’s definitely true, too.

But the reality is that it’s genuinely difficult to think of anything else that could be happening in Britain today that would be directly affecting so many people or businesses. With apologies to the “not everyone lives in London” brigade, that’s why it’s leading the news today.

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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