Foreign policy barely gets a mention in this US election, but for the rest of the world the outcome on 3 November will arguably be the most consequential in history.

All US elections have a global impact, but this time there are two issues of existential importance to the planet – the climate crisis and nuclear proliferation – on which the two presidential candidates could hardly be further apart.

Also at stake is the idea of “the west” as a like-minded grouping of democracies who thought they had won the cold war three decades ago.

“The Biden versus Trump showdown in November is probably the starkest choice between two different foreign policy visions that we’ve seen in any election in recent memory,” said Rebecca Lissner, co-author of An Open World, a new book on the contest for 21st-century global order.

In an election which will determine so much about the future of America and the world, the Trump campaign has said very little about its intentions, producing what must be the shortest manifesto in the annals of US politics.

It appeared late in the campaign and has 54 bullet points, of which five are about foreign policy – 41 words broken into a handful of slogans such as: “Wipe Out Global Terrorists Who Threaten to Harm Americans”.

The word “climate” does not appear, but there are two bullet points on partnering with other countries to “clean up” the oceans, and a pledge to “Continue to Lead the World in Access to the Cleanest Drinking Water and Cleanest Air”. (The phrase ignores a series of US scandals about poor water quality – and the fact that millions of Americans can no longer afford their water bills.)

The US remains the world’s second biggest emitter of greenhouse gases and the average American’s carbon footprint is twice that of a European or Chinese citizen.