With Donald Trump almost certain to be the Republican’s US presidential nominee, business elites are already rationalising his second term. “He was kind of right about Nato, kind of right on immigration,” Jamie Dimon, of JP Morgan Chase, said in Davos last week. “He grew the economy quite well. Trade. Tax reform worked. He was right about some of China.”

Many Republicans similarly assuage their conscience about backing Trump, despite his vulgarity and anti-democratic tendencies, by pointing to his policy successes. Sure, he might have sullied American democracy by seeking to overturn an election, but didn’t his tax cuts, deregulation and appointments of business-friendly judges help to deliver a “great” economy?

David Stockman’s book, Trump’s War on Capitalism, fiercely challenges this view. Stockman, who was director of the Office for Management and Budget under President Reagan, makes a case that might have been put forward by a braver version of Ron DeSantis: that Trump’s economy was mediocre, that he failed to deal with America’s longstanding afflictions and that, on policy, he was a “big spender, easy money-man, hard-core protectionist, immigrant-basher … and all-around Big Government statist”.

Presidents have far less control over economic outcomes than they imagine, which makes Trump’s boastful claims more outlandish. He “inherited the positive momentum of a ripening business cycle”, Stockman says, but the subsequent economic performance was hardly stellar. Annual growth of real final sales during Trump’s term, at 1.5 per cent, was the lowest of any president since 1954. Even discounting the pandemic, his record barely surpasses the Great Recession-afflicted terms of presidents Obama and George W Bush.

Under Trump, pre-pandemic job growth fell short of Obama’s second term and real GDP per capita growth, while reasonable, was nowhere near as high as during the tenures of presidents Reagan or Clinton. In any case, giving Trump a free pass for 2020 is wrong, says Stockman, for when Covid-19 hit it was he who encouraged one-size-fits-all lockdowns nationwide that sank GDP. This opened the door to the eventual $6.2 trillion in Covid-19 relief spending (about $19,000 per person) and Federal Reserve money-printing that exacerbated inflation.

Trump’s vaunted corporate tax cut had some benefits but racked up more debt, while his “deregulation” amounted to little more than tweaks to certain rules, according to Stockman. Trump’s real legacy was rubber-stamping vast spending packages driving high and rising budget deficits, even in sanguine macroeconomic conditions before the pandemic. Trump failed to make hay while the sun shone, sidestepping much-needed immigration, old-age entitlements, and monetary policy reform. Instead, he publicly pressured Jay Powell, Federal Reserve chair, to push interest rates to zero in 2019.

Other Trump impulses harmed economic growth. His obsession with infrastructure and “Buy American” provisions fuelled subsidy frenzies, escalating under President Biden. His toxic stance on immigration, deeming foreigners as welfare parasites, job-stealers and incipient criminals strained a stagnating prime-age workforce. His conviction for protectionism ignited a tariff war with China, ramping up businesses’ input costs while failing to address the root cause of America’s trade imbalances.

Stockman surely overstates the case. The economy ticked along pre-Covid-19, hardly suggesting huge harm from Trump, while most presidents would have reacted strongly to the virus. Unemployment fell to historic lows, a testament to America’s flexible labour markets, and stemming the flow of regulation delivered businesses welcome certainty. It also seems churlish to blame Trump for the range of problems Stockman associates with loose monetary policy, especially considering Stockman’s unconventional views on the matter.

Yet, overall, Stockman’s critique is powerful because it’s grounded in policy analysis, rather than concerns about Trump’s conduct. Stockman shows clearly that Trump has no interest in traditional conservative goals such as balanced budgets, free trade, sound money or smaller government, even if he has “all the right enemies”. That so few Republicans care is a damning indictment of their lack of principle.