Well that is a big and complicated question. With multiple answers. But the rot set in under Tony Blair. Having triumphed in 1997 he won two more general elections, but lost votes at each until at the fourth, under Brown’s leadership, the loss of votes for Labour since 1997 totalled nearly 5 million.
In the pursuit of power Blair shifted Labour from its working class roots to a left of centre middle class party, which embraced most of the dogma of Thatcherism and did little to correct the terrible imbalances in her economic model. It ignored or took for granted the Labour industrial heartlands north of London and especially Scotland.
So the working class either stayed at home or voted Lib Dem or later UKIP and SNP. Corbyn in his first general election in 2017 recovered Labour’s lost votes in England and Wales, coming in just short of thirteen million. That compared to Blair’s final 9.5 million, Brown’s rock bottom 8.6 million and Milliband’s 9.3 million, which included a wipe out for Labour in Scotland.
In 2019 Labour dropped back to 10.3 million, which was by no means its worst performance in votes, but it was a disaster in seats. This was due to the famous crumbling red wall. That happened because voters there, having being energised in 2017 by Corbyn’s left wing offer, lost faith in Labour. The seemingly endless and intractable row about anti-Semitism, the muddles and many faceted strands of Labour’s Brexit policy (Kier Starmer directed), the fear that it had become a Remain party and the economic illiteracy of its spending plans, tipped lifelong Labour areas to turn blue with anger and frustration.
So to blame any individual, even the colourless Starmer, who is deadly against the blustering Boris in the Commons, but becomes invisible in a crowd of three on the campaign trail, is pointless. It is not all bad news. Labour had some good wins, especially in the regional mayor contests, and my have laid the foundation to build a different kind of Labour fit for the modern age, when so much is wrong in the country and crying out to be put right.
First the party has to unite, second build on its strengths and third reconnect with voters in its heartlands, at least as well as it seems to be connecting in Wales and some of the regions. A while back I wrote a little book called Turn Left To Power. The biggest problem for Labour is that it is Boris who has turned left. And he certainly has gained power. He thinks he can keep it. Labour’s mission is to take it back.