A more stable government means Mr Trump would have far more scope to press ahead with his objectives, primarily on trade, Mr Ross said.
Mr Trump kicked off a trade war with China in 2018 by imposing significant tariffs on imports. Now, he has proposed a blanket 10pc tariff on all imports and charges as high as 60pc on goods from China.
The idea of free trade is “a myth”, Mr Ross said.
“This wonderful, enchanting theory that as a country you would make and export what you do best, and you would import what you do worst. The only problem with that is that it is not the way it works. Everybody wants to do more,” Mr Ross said.
Before the Second World War, trade tariffs were the major source of revenue for the US government, but these charges were largely lifted as the US tried to rebuild Europe and Asia during the post-war recovery, Mr Ross said.
“That probably was a good idea at the time, but I think it should have been time-limited, maybe for 10 years. But instead we made it permanent.”
Yet Mr Trump’s language on trade may be misrepresentative of what he would actually do. The Republican candidate is, at his heart, a PR machine.
“He often speaks in metaphors without clearly identifying them as such,” said Mr Ross. “When he talks about – as he did even in his first campaign – gigantic tariffs on everything coming in, that is really meant to be a way to message to the public that he is going to be really tough on trade. But you shouldn’t fall into the trap of taking those things too literally.”
The same is true of Mr Trump’s language on Ukraine, he added. The presidential candidate has repeatedly claimed he will bring a quick end to the war and has made clear signals that he will row back on US support for Ukraine.
Yet Mr Ross’s view is that it is “essential that we win”, not least to stop the spread of wider conflict.
“But I think there’s a more important reason, frankly, both for Ukraine and also with Israel, and that is, think back, how did World War Two get started?
“China, Russia, North Korea and Iran, they all always support each other. While I don’t know if they do literally have a mutual defence pact, they are certainly acting like it. So I am very worried, given that this could well be the beginning of the formation of a new axis of powers.”
‘Tories started the tax rises’
Mr Ross’s book is published on the eve of Rachel Reeves’s maiden Budget, which is, in cash terms, expected to be Britain’s biggest tax-raising fiscal event in history.
Ms Reeves is expected to announce increases in employer National Insurance and rises in capital gains tax. She will also press ahead with Labour’s manifesto pledge to tighten the non-dom tax regime, which allows wealthy internationals to avoid paying tax on overseas income unless they bring it into the country.