Austerity did not happen because of the previous Labour Gov spending plans.
Nobody has said it did, but after the 2 years of following the previous Conservative spending plans the previous Labour government who had publicly went on record as saying there was no more boom and bust does have some part to play, especially since we all have 2020 vision and say we should have followed Keynesian economic theory so should have saved during the boom.
We could also highlight that in 2010 it was a poisoned chalice and all political parties was saying austerity was needed.
The UK govt had to bail out financial banks and that is what caused the massive increase in debt.
Was the right decision by Brown, was copied across Europe, both understood that it was can kicking exercise so it's difficult to call it idiological or blame the tories for it as well.
Before the financial crisis and recession , Conservative party’s spending plans were pretty close to Labour’s and they were def not asking for tighter financial regulation of banks which would have stopped the financial crisis.
Trying to pass the book onto the opposition when it was those in power who was implementing in control of the sitution is text book 'no u' tier argument.
I kind of expect a 'not true labour' argument or some hark back to thatcher to really show your critical thinking.