I've posted this before on other threads.
About a year ago, I read an article about a professor in PPE who devised a software programme into which he entered key phrases from the manifestos of all UK party leaders over the last fifty years. The software analysed and then produced a line chart placing each leader on a Left/Right spectrum.
Unsurprisingly, the biggest gap was between Neil Kinnock and Margaret Thatcher. What surprised me, though, was that Tony Blair was to the right of John Major. It does explain 1997, though, and also explains much of the angst between Blairites and Corbynites today.
On the spectrum, Tony Blair was also still slightly to the right of Theresa May, which also explains much of the unhappiness within the Conservative Party (Brexit aside).
Jeremy Corbyn is very very left of Neil Kinnock.
I cannot, for the life of me, remember where I read the article. I've searched for it since in vain. It predates Boris's leadership. However, my own view is that Boris is occupying the space vacated by Tony Blair (pre-Iraq). He is - and I'm sure there are many who will disagree about this - a One Nation Tory. One Nation Tories are on the left of the Party, as opposed to Thatcherites, who are on the right of the Party.
In other words, Boris is as left as the Conservatives will tolerate, and as right as traditional working class Labour will tolerate. In my view. It's a very careful positioning.
The Momentum version of Labour has been comprehensively rejected and the Labour Party will have to decide how to respond to that. I too want to see a functioning Opposition; our democracy depends on it. However, Labour will either have to change its policies or change the electorate.