Leave won. Making an appeal to cater to the whims of British democracy holds very little weight at the moment.
If getting an elected with a majority means copying the UKIP manifesto, that still doesn't make it right. I'd rather have a Labour party that stands for values worth a damn than one willing to abandon any and all principles in order to win.
The whims of the British public aren't set in stone and entirely unchangeable. They vary over time as politicians do better or worse attempts at persuading the public. There was quite some difference between Hague and Blair, or Brown and Cameron; in both situations the latter was better at persuading the public. At the same time, there is a "stickiness" to opinions; you can't wildly overturn everything the public thinks overnight. The further you are from where the public sits now, the harder the task of persuading them becomes. So you face a game of tiny, tiny steps: you fight for every possible leftwing inch, and over decades, those inches become a yard and then a mile. That's where the principles are: they're at the end of that mile, and you really do have to fight for them. They don't happen overnight.
This process requires two skills: a persuasive and apparently competent leadership, and a policy platform that is precisely as leftwing as the leadership's persuasiveness allows for, and no more (and no less!). Right now, Corbyn is neither persuasive nor competent, and the party's policy platform is far away from the public on most issues. So what you're doing... is conceding everything to the Conservatives. The less appealing Corbyn looks and the further he goes from the centre, the more appealing the Conservatives seem by contrast, the more they win the public mindset, and the less likely we ever are to reach our principles at the end of the mile.
There is, absolutely, a manifesto that Labour can run and win on that is to the left of the Conservatives. We know that because Blair did it. There's almost certainly one to the left of Blair, even, looking at the size of his first two majorities - he was almost certainly too small-c conservative and risk averse. But even if there wasn't... gay marriage, Sure Start, the national minimum wage, devolution, NHS funding increased by 25%, a mass redistribution of wealth, a continued reduction in childhood poverty - these things are all great. No, the Blair and Brown governments were not perfect; far from it - they had an absolutely disgusting stance on disabled welfare, Blair's foreign policy was frankly mad, they didn't do enough to reinvest in reskilling and retraining in economically failing areas. But they were miles better than the Conservatives.
So you're creating this massive false dichotomy where we either have principles and lose or have no principles and win. No: we accept that principles are something you achieve in fifty years, not five, and to implement them, you need to win. And I say this as a pretty ardent socialist.
