The Americans have a saying: “you break it, you own it”. In the world of climate diplomacy, the maxim is “you host it, you own it”. In Copenhagen in 2009, the Danes owned a disastrous climate event that broke up in rancour. In Paris in 2015, the French owned the successful agreement.

The 2020 UN climate change conference, known as COP26, which will be taking place in Glasgow in November, could be Copenhagen or Paris, or somewhere in between. Ownership and responsibility will firmly rest with the government. The events of the past few days have proved beyond doubt, however, that we cannot leave it to the government alone. We all need to take ownership of this event.

In case you are not convinced, and feeling a bit inert, let me persuade you that this really matters: 2020 was the year nominated in the Paris agreement for when the world had to narrow the gap between its noble aspirations to limit global warming to 1.5C and its country-by-country commitments, which currently add up to, at best, 3C of warming. Given we only have a decade to decisively turn things around, we just cannot allow Glasgow to fail.

This is a massive moment and the government has so far simply been unable to get to grips with the importance and the complexity of these negotiations, as illustrated by the fiasco over the appointment and sacking of Claire O’Neill, and the rather public – and so far fruitless – search for a president for COP26.

However, it’s not just the government that needs to step up. Success or failure will in part depend on how much it is made to care about the issue. That depends on all of us. If the government thinks it can slink out of Glasgow without too much notice being taken, it may well decide other priorities are more important. We cannot let that happen.

That means in practice, first, that the government must feel the pressure to act here at home. This summit is about persuading other countries to ratchet up their ambition. To succeed, we need to ratchet up ours and quickly.

Britain has committed to net-zero carbon emissions by 2050 but currently our 2030 target does not reflect even that ambition. As we seek to persuade others to do more in the short term, we need a 2030 target of significantly greater ambition that puts us on track for net-zero by 2050.

This more ambitious target must be accompanied by action in every sector, and a budget on 11 March that focuses on this issue, and includes a proper 10-year plan to decarbonise homes over the coming decade, while cutting bills and creating jobs.

Second, crucial to the success of Glasgow is a strong alliance with the EU. Before Paris it was the US-China axis that made the crucial breakthrough. This time, with the US off the pitch under President Trump, the best hope is that the EU, which is responsible for 10% of global emissions, and China can act in concert to raise the level of ambition.

Third, we have to recognise that every lever of government must be part of making this agreement happen, particularly around how public and private finance supports or thwarts the transition. That includes mobilising public and private finance for developing countries, ending international government support for fossil fuel extraction and building on the appointment of Mark Carney as the COP special envoy to ensure proper regulation of financial and corporate institutions around climate risk.

Fourth, over and above actions by national governments, Glasgow must power forward coalitions of states, cities, businesses and civil society around the path to net-zero, including the phasing out of coal, and petrol and diesel vehicles, divestment from fossil fuels, and addressing deforestation.

There are millions of people who care deeply about this issue in the UK and beyond. Extinction Rebellion and the pupil climate strikers have changed the terms of the debate over the past year. It’s up to all of us, including our brilliant NGOs, to ensure this moment sees the biggest mobilisation on the climate emergency in British history.

You may wonder what the point of mobilisation is if the geopolitical forces are so badly aligned. The answer is there is no other option. The only way we will get change on this issue is showing government that there is a big political coalition that believes this really matters. Positive momentum from Glasgow is essential. We all need to step up. We all need to own it.

Our future, and that of our children and grandchildren, is in the balance. Only by acting now can we prevent future disaster.

• Ed Miliband is Labour MP for Doncaster North and a former climate change secretary