The next prime minister promised nothing less than the biggest change in British politics in 40 years in his first speech as Labour leader.

As Andy Burnham waited to enter the hall for the moment he has dreamed about for at least 16 years, he told us he was feeling "good… ready". In the course of a whirlwind four weeks, every wing of the parliamentary Labour Party has anointed him as the only person able to reverse their electoral predicament. But this was a speech where Burnham set his ambitions far higher than the conventional measure of political success: elections. Understandably, given this was a Labour Party event, he spoke about his desire to change the culture of the Labour Party. There are plenty of people from different Labour factions who bear the scars of failed attempts to do that, as well as others who see it as an undesirable goal: not so much unity of purpose, they argue, but unity over purpose. "Four decades of neoliberalism" had followed, he said, damaging traditional working-class communities in cities and towns as well as rural and coastal areas. Doing so, he said, would amount to no less than "the most significant change moment in our politics for 40 years". It will not have been lost on any Labour MPs listening that in making this argument Burnham is not only criticising Thatcherism, but also the accommodation with elements of it which he clearly believes the New Labour governments he served represented.