It's a tribute to the uniquely low electoral expectations that Jeremy Corbyn inspires that calls for his resignation today are muted and unconvincing. It is safe to say that any other major party leader who had just lost a seat - to the Government, in a by-election, in a constituency that they had held for 80 years - would be in for kicking from their own side. But despite the very real historic significance of the Copeland result, Corbyn is unlikely to be forced to give an ashen-faced goodbye speech in the next few days. His safety is in part a product of Labour's structural nightmare and in part a product of the veneer of invincibility that two leadership victories have lent him; because of both, he will leave at a time of his choosing.
Labour is in existential trouble, post-referendum. All parties in British politics are coalitions of a sort and since the late 80s, Labour has - sometimes successfully, sometimes less so - forged its coalition as an alliance between the public sector middle class and the traditional working class. Europe - both on its own and as short-hand for an array of liberal, Blairite assumptions - splits that coalition down the middle. Labour's active membership, like its MPs, are overwhelmingly pro-Europe, white collar, cosmopolitan and degree educated. Huge swathes of Labour voters - particularly in Northern seats like Copeland - share few of these attributes.
The pressures placed on that coalition by Brexit are extreme - as Stoke shows, Labour can still limp home, but 40 year old presumptions about who will always give Labour their vote are no longer certainties. And that presents the party with a horrible challenge - they are between a rock and a hard place. In affluent, middle class seats Labour voters are giving the resolute remainers in the Lib Dems a second look. In working class seats outside of the metropolises, both the Tories and UKIP pose a threat. Trudy Harrison ran a campaign in Copeland focused on Brexit and on nuclear energy - two areas where Labour is confused, at odds with their Leader and fundamentally unconvincing in either direction. Of course, the particularities of Copeland as a constituency (overwhelmingly Leave, home of Sellafield) helped the Tories out. But with a few tweaks this is messaging that could help the Conservative Party do to Labour in non-metropolitan northern seats what the SNP have done to them in Scotland.
This structural weakness in Labour's position is not all Jeremy Corbyn's fault. No-one on the social democratic Left has plotted a convincing alternative course. And across the West, parties that mirror Labour's electoral coalition are facing similar challenges. But if Ed Miliband had led his party to last night's result he would have expected a serious and potentially fatal crisis in his leadership. Corbyn and his allies have space and time to think. That is because the Parliamentary Labour Party blew their chance to kick him into touch by launching Owen Smith's disastrous challenge last year. The party is exhausted. It lacks the emotional energy to remove their Leader - despite the undeniable dampening effect that he has had on the Labour vote in both Stoke and in Copeland. There is also a strong feeling in the PLP that, having stood and won twice in leadership elections, Corbyn must now face the electorate at a General Election. The only way to convince the membership that Corbynism doesn't work on the doorstep is to show them on the doorsteps. This explains the pressure from some on the Left - such as journalist Owen Jones - on Corbyn to stand aside voluntarily so as not to tarnish authentic socialism forever. The best hope of an ouster now comes not from old enemies on the old right; the only viable threat now comes from the Left. But he and (more importantly) his immediate team are determined that they must be guaranteed at least a shot at one of their own replacing him; the Left will only act if John McDonnell is successful in changing the party's rules to ensure a Left candidate is on the ballot when the next leadership election comes. Frustrated MPs may well decide that it is worth supporting his proposals - a slim chance of a more sympathetic leader may be worth the gamble. For the Tories, the results in Copeland and Stoke are cause for celebration. May has shown she can achieve something that always eluded Cameron - real and meaningful gains from Labour in seats that are working class and Northern. She has also demonstrated that the route she has set through Brexit has resonance with voters who opted to Leave. And given her flimsy majority, every seat counts.
Meanwhile, Paul Nuttal's suicide bombing of Stoke will further neutralise UKIP to the Right - giving May room for manoeuvre. But Tories in London and the South are worried about Tory-Lib Dem switchers - concerned that the party's hard line on Brexit is turning off middle class professionals. What's more, a growing number of MPs feel emboldened to call for a General Election. They fear the consequences of economic shock once Article 50 negotiations actually commence - why not capitalise on the party's popularity now rather than risk a change in fortunes? May has reason to feel pleased with herself and with her party, but victory brings its own challenges.
Meanwhile, the Liberal Democrats continue to see the benefits of their clear, pro-Remain messaging. They are outperforming their polling in elections once more, gathering support in London and achieving some level of cut-through with dismayed centrists of the Left. There are seats across the south and in the cities where the yellow peril once again strikes fear into the hearts of incumbents from both parties.And so, on we go. As one rule of politics is broken after another, as historical precedents and previously safe presumptions are shoved aside, nothing seems to make much of a difference. May is still the safest and most empowered PM since Blair - despite not having been elected to the role. Corbyn remains immovable, despite being phenomenally unsuccessful and unpopular. The Lib Dems continue to hover on the brink of a bounce back. And Brexit rumbles on.