The sad fact is that America spent perhaps $5 trillion in Iraq and Afghanistan and has little to show for it, while its principal competitors, Russia and China, invested a minuscule fraction of that amount in advanced weapons technology and leapfrogged American technology. That places inherent constraints on American strategic action. Washington may object to Russian bombing in Aleppo, for example, but is in no position to force the Russians to stop. By the same token Washington may object to China’s acquisitiveness in the South China Sea but can do nothing to counter it (as the Philippines noticed before declaring that they wanted to change sides and stick with China, the evident winner).

There is no short-term fix to such problems. There have been many calls for Nato to stand up to the Russians, but little explanation as to just what that might entail, once the deployment of stealth fighters to Syria is ruled out for compelling technological reasons. Under the best of circumstances, Nato would require some years to develop effective countermeasures to the present generation of Russian and Chinese military technology. Trump has promised to rebuild America’s military, and his election occasioned a leap in the share prices of the major American defence contractors, as well as British Aerospace.

A large and sustained increase in American defence spending would be of economic benefit to Britain, whose defence industry is closely integrated with America’s. It is noteworthy that of all the major currencies, sterling was the only one to rise after Trump’s election victory. Markets evidently believe that a post-Brexit UK and a Republican-led America will have a great deal to do together, and that the UK’s economy may benefit from the Special Relationship. It does not seem likely that Donald Trump and Theresa May will rekindle the natural sympathy of Ronald Reagan to Margaret Thatcher, but there is considerable room for the Special Relationship to evolve to both countries’ benefit.