SOCIALISM, Post World War 2, put britain back on her feet.
UK DEBT % GDP - fiscal stance 1900 to 2000
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Clement Attlee saved the British economy post world war 2, with an aggressive 5 years plan of collectivisation and nationalisation.
Post world war 2, there was an concensus to continue with socialism and the general Keynsian direction.
Thatcher came to power in 1979 and squandered those assets because of a desire to follow monetarist doctrine.
That left labour with an economy that depended on the sale of the nations silver ware to maintain cashflow.
Perhaps in desparation, the labour party allowed the banks to grow as means to plug the gap in the nations economy.