We have had fantasy football & cricket, and now we have Labour fantasy economics and politics. Even 'moderate' Liz Kendall has made the statement that "Labour overspending did not cause the collapse of (American financial services giant) Leahmen Brothers." Nobody claims that. It's a deliberate straw man argument.
In America the Federal Reserve (the US central bank) kept interest rates artificially low and created a consumer boom in order to buy cheap Chinese exports. American banks were encouraged to take extreme risk in investment banking and sell sub-prime mortgages, and oversight of these activities was reduced. Growth in the economy meant increasing tax revenues could be used to increase government spending. The boom could not last and financial collapse caused a massive bust.
Here in Britain the Bank of England kept interest rates artificially low so we could all buy cheap Chinese goods, British banks made risky investments and took on sub-prime mortgages, Gordon Brown reduced oversight of the City and increasing tax revenues were used to increase public spending. The boom did not last and turned to bust. Gordon Brown had to use massive sums of taxpayers' money to save British banks from the collapse he helped to cause.
Just what was the difference between America and Britain?-of course, nothing. It was the British Labour Government which nearly bankrupted our country. None of the Labour Party leadership contenders appear to have learned any useful lessons at all and still inhabit an economic fantasy world.