Penthesileia Oh - I agree that 1900 is just as arbitrary as 1945.
Ultimately, it boils down to this. Is Britain, long-term, going to be a right-wing country, or a left-wing country?
It is pretty clear on individual policy positions.
In terms of the EU I think the answer is settled, and pretty obvious. Similarly, in terms of the NHS.
In the final decades of the 20th century, though, Reagan and Thatcher exposed communism for what it truly was, Tony Blair accepted Margaret Thatcher's market reforms in full, and capitalism comprehensively defeated socialism.
The economic disputes between left and right now are generally less pronounced now than ever before, because on the big economic arguments the left totally conceded. Remember there isn't much difference really, in macroeconomic terms, between Labour's plans and the Tory plans - though they will both dispute this for political purposes.
Similarly the right has had to concede pretty much entirely on social policy, but I happen to agree with most of these concessions as I am a social liberal.
The credit crunch had in it the potential to be a global rebirth of the left, but instead, the left is getting smashed all over the world as people realise the consequences of debt, and the importance of sound public finances. If the crucial importance of the little-c conservative notion of balancing the budget can be firmly instilled in the current generation of young people, it will be a big strategic victory for the right.