This week Alexandria Ocasio-Cortez, the newly-elected socialist congresswoman for New York, joined the Justice Democrats and the Sunrise movement at a sit-in at the office of Nancy Pelosi. The 29-year-old - the youngest woman ever elected to the House of Representatives - did so to demand that the Democrats immediately develop a Green New Deal for the US economy. This programme – a huge, co-ordinated programme of public investment aimed at decarbonising growth – would be the most radical and transformative economic proposal put forward by any US party since Franklin Roosevelt’s presidency.

The rationale for targeting Pelosi – the incumbent House Minority Leader and aspirant Speaker - was clear. As soon as the Democrats reclaimed the lower chamber, Pelosi used her platform to suggest that the party “work together” with Donald Trump to promote a bipartisan agenda in the interests of all Americans.

As with Barack Obama’s emphasis on bipartisanship, this sounds appealing. But it neglects the conflict that exists at the heart of US society: the division between those who live off work and those who live off wealth.

Trump seeks to mask this economic divide by scapegoating alternative adversaries – the US’s immigrant and Muslim populations - while pursuing policies that serve the interests of his true constituency: the wealthy elite. Tax cuts, deregulation and the erosion of the social safety net have all served to redistribute the wealth produced by the working people of America to corrupt and unaccountable elites.

That Pelosi would even consider compromising with such a man - and such a programme - is revealing of the priorities of the Democratic establishment. Because the old Democrats, who receive billions of dollars from Silicon Valley and Wall Street, have as little interest in exposing the wealth/work divide that shapes the US economy as Trump himself.

But the new Democrats - representatives like Ocasio-Cortez, Julia Salazar and Rashida Tlaib – are unafraid to recognise this fundamental conflict. They campaigned on reducing the profound inequalities of power and wealth that distort American democracy and are now fighting to translate their successful campaigns into concrete policies.

The Green New Deal is perhaps the most developed agenda being promoted by this insurgent movement. Spearheaded by Ocasio-Cortez, it draws on crucial research by economists such as Ann Pettifor and Mariana Mazzucato, as well as international organisations such as the United Nations Conference on Trade and Development (UNCTAD) and the United Nations Environment Programme (UNEP).

Like the New Deal of the 1930s, the Green New Deal would be a coordinated public investment programme aimed at expanding economic demand by increasing employment and wages, whilst also raising long-term productivity. The philosophy behind the GND is therefore classically Keynesian: investment in physical, social and technological infrastructure will pay for itself in the long-run by expanding demand today and increasing productive capacity tomorrow. The unprecedented stimulus programme introduced by the Chinese state following the 2008 financial crisis demonstrates how valuable even a more modest programme can be.

But the GND has more far-reaching aims. As the IPCC’s recent report warned, and as the ferocious fires in California have demonstrated, the world is edging towards climate apocalypse. If we fail to fundamentally change the basis of production, there won’t be an economy by the end of this century.

As such, the GND doesn’t simply aim to boost demand, it aims to transform the nature of the US economy. The proposals include converting the nation to 100 per cent renewable energy sources, decarbonising key industries, and investing in new green industries and technology. The foundation for these changes would be a dramatic increase in state spending – perhaps alongside a federal jobs guarantee – accompanied by tax rises on the wealthiest individuals and the largest corporations.

This represents a radical break with the depoliticised narrative too often advanced by the climate movement itself. Rather than insisting that “we are all in this together”, those crafting the Green New Deal recognise that global warming and capitalism are inextricably linked. Just a hundred companies are responsible for producing 70 per cent of global CO2 emissions – most of them located in the global north.

Meanwhile, climate change, and the economic damage associated with it, impacts most heavily on the poorest. The wealthy, as usual, have found ways to protect themselves: a point vividly illustrated by the private firefighters Kim Kardashian and Kanye West hired to shield themselves from the Californian blaze - an emblem of late capitalism. In short, there will be no climate justice without economic justice, and no economic justice without climate justice.

The Democrats now face a defining choice: will they follow Pelosi’s path, or Ocasio-Cortez’s? The former, which would represent capitulation to Trumpism, Wall Street, and corporate power, can only end ruinously for the Democrats and America itself. The latter might antagonise the party’s wealthy backers, but it might also the represent the first step on the long path towards saving the planet.