Liberalism died in 2016. This bold statement has been made by both right and left wing media in recent months. But what is liberalism - and can such a broad idea really be that vulnerable?

Edmund Fawcett, author of Liberalism: The Life of an Idea, charts the rise and rise of liberalism, from Gladstone's social reformers to the economic liberalism of Margaret Thatcher. Sir Oliver Letwin MP played a key role in the Conservative Party's adoption of more socially liberal policies after 2005. He tells David Aaronovitch about embracing gay marriage, advocating green energy, and emphasising social justice.

But is liberalism a luxury of the middle class? Lynsey Hanley discusses the link between social status and social conservatism. She explains why the working class may reject liberal values in defiance of the metropolitan elite.

Producer: Hannah Sander Researcher: Kirsteen Knight.

The Emily Thornberry One