I have a dream: a lean, green dream. Many people share this aspiration towards a defossilised, minimal waste economic model. This Sunday 310,000 green believers peacefully marched through Manhattan to show their commitment to climate protection.

Manhattan’s People's Climate March eclipsed one of the largest political rallies in US political history: the quarter of a million who thronged Lincoln Memorial to hear Martin Luther King’s ‘I have a Dream’ speech. 1963’s Great March on Washington changed race relations in US legislation and US society irrevocably. The Climate March was 3.5km long in Manhattan and was marked by more than 2000 other climate events across 166 countries calling for a change to superpolluting economics.

The Climate March represents a new mass movement that aims to give climate and natural resource concerns a political voice, which unites the political left and right, and involves people from all creed, colour, and background.

UN Secretary General Ban Ki-moon; Al Gore; Hollywood leading men Edward Norton and Leonardo Di Caprio; singer-songwriter Sting; UN climate envoy and Ireland’s first female president Mary Robinson; US Secretary of State John Kerry; and Robert F. Kennedy Jr.walked alongside Hurricane Sandy victims, and disenchanted protestors to call for the politics of the earth to be enfranchised and enshrined into economics and business. Peaceful protestors in 166 countries were far, far more eclectic. Climate change is an ‘everybody issue’ now. Around 40,000 people including actress Emma Thompson; designer Dame Vivienne Westwood; and musician Peter Gabriel took part in a similar march in London.

The Climate March was staged to coincide with this week’s UN summit – the first time so many heads of state have met to discuss climate change since 2009 in Copenhagen – to bolster preparations for a global climate agreement to lower emissions in Paris at the end of 2015. However China’s President Xi Jinping will not be attending the summit – sad face. Nor will India’s Prime Minister, Narendra Modi – despairing face.

There is no plan(et) B. But another economic model is possible, one that is defossilised, and respects natural resources. This is a dream that hundreds of thousands are willing to turn into our future reality.