Another month, another dire UN climate warning. We’re “hurtling towards disaster”, said Secretary-General António Guterres last week, calling for immediate global action.

Meanwhile the Ukraine war grinds on. The gulf remains between China and the West. Government-subsidised companies make record profits from fossil fuels while skimping on clean energy investment. Promises around national emissions targets and money for poor and vulnerable countries continue to fail.

In a fractured, distracted world, international agreements won’t save us without action on a large scale by the world’s richest nations. What we need is a country with a big, beefy economy and voter base, and enough clout and idealism to take others with it on the strength of its beliefs and knowledge. A country that we know can take a lead because it’s done it before.

I have always regarded capitalism as profoundly undemocratic. For most of my life I would have scoffed at the idea that people focused on getting rich might help us out of any kind of pickle, let alone the ultimate pickle, climate change. But the British economist-philosopher Martin Wolf has persuaded me otherwise.

The radically different ideas of capitalism and democracy can never sit easily together, but Wolf, in his landmark 2023 book The Crisis of Democratic Capitalism, makes a powerful case that having together pulled the global economy out of the rubble of World War II, these awkward twins are the world’s best hope for slaying the climate dragon.

capitalism and democracy … having together pulled the global economy out of the rubble of World War II, these awkward twins are the world’s best hope

The key economies in this scenario are autocratic China on the one hand and wealthy democratic nations led by the US and the EU. Our hope lies in the democracies, but they’re under the pump, none more so than America.

That country’s established institutions, procedures and principles, like universal adult franchise, separation of powers and, crucially, equality under the law, have made it a bulwark against tyranny. Now, Donald Trump is testing it as never before.

Trump is yet to be held accountable for promoting the big lie that he won the 2020 election over Joe Biden and stirring up the subsequent assault on the Capitol. Already facing all manner of accusations around myriad misdeeds, last week he was in federal court on charges of violating the Espionage Act and conspiring to obstruct justice.

Time is the enemy in securing justice, and Trump is a master of legal delay. With a judge he appointed leading his first federal trial, Supreme Court ethics under attack and Congressional cronies doing his every bidding, he can stretch this out through next year’s presidential election – in which he’s the leading Republican candidate.

After last week’s court appearance, Trump told adoring supporters that his enemies, “they”, sought to silence him “because I will never let them silence you”: the classic attitude of a messianic cult leader.

It’s been said that while history never exactly repeats itself, it does rhyme. The nearest rhyme to today is America in 1940. As war spread across the globe, the country’s wheelchair-bound leader through the Depression, Franklin Roosevelt, was challenged by a Republican party influenced by wealthy supporters of Adolf Hitler.

As it happens, Americans turned their backs on tyranny and voted for Roosevelt in 1940, ensuring that the US joined the war for democracy. He died in 1945, three months into his fourth term, but his celebrated place in American and world history remains secure.

Like Roosevelt in 1940, Joe Biden is ageing. Like Roosevelt he’s up against well-financed right-wing extremists. But he’s experienced and resilient, and we can’t write him off.

While climate change is not yet front and centre in voters’ minds as Hitler was back then, it will be, maybe sooner than anyone expects. Leadership will have to come from all quarters including Australia. And when the action starts, who knows what is possible?

While climate change is not yet front and centre in voters’ minds as Hitler was back then, it will be, maybe sooner than anyone expects. Leadership will have to come from all quarters including Australia.

Of course there are little holes in this future hypothesis. Nasties include fossil fuels, war, displacement, famine, extreme weather, Trump, governance and accountability failures – as well as megalomania and disinformation at home and abroad. Did I say little holes? “Gaping” is probably the word I’m after.

But against all that is what we know is possible. The world was in ruins in 1945, but American optimism was infectious. It got Europe and Japan back on their feet and delivered us international human rights law (with more than a little help from our own Bert Evatt, first president of the UN General Assembly). And the world responded.

Now we all have to do it again. Obstacles are immense, but they are there to be overcome. We just have to do it.