It is a sobering thought that the US is racking up as much debt-to-GDP accumulation over 20 years as it did over two world wars and the Great Depression combined.

You can blame it on the Lehman crisis and Covid, overlaid with Trump’s unfunded tax cuts and Biden’s unfunded multi-trillion fiscal spree, but behind that lies a structural rot across most of the federal budget.

China’s fiscal deterioration has been just as bad. The difference is that China funds its own borrowing (for now) from high internal savings. Foreigners have some $25 trillion of net debt claims on the US government and US corporations.

America’s net international investment position has gone from near balance a generation ago to minus 62pc of GDP. Part of that is the distortion of the strong dollar. A big chunk is not. America is selling the family silver to live (so is Britain).

"It is alarming to us, and should be to other investors, too. What is even more alarming is the lack of concern on the part of the US policymakers,” said Stephen Jen from Eurizon SLJ, who advises Asian sovereign wealth funds.

"Foreign investors should not be blamed for starting to wonder if the US Treasuries and the dollar are still safe. We believe the US debt problem will have consequences for the markets in the not-too-distant future,” he said.

The immediate effect of the debt deal is contractionary. The US Treasury has added $500bn of financial liquidity since early February by draining its account at the US Federal Reserve in order to keep the government going.

This has acted as a form of quantitative easing (QE) and overwhelmed the Fed’s quantitative tightening (QT), flattering the spring rally on Wall Street.

The process is about to go into sharp reverse as the Treasury taps the debt markets to rebuild depleted coffers. The next few months will see synthetic QT on steroids.

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To continue pushing this Rooseveltian spending agenda after the economy was at near full capacity and in a V-shaped recovery was playing with inflationary fire, but it also guaranteed that interest costs would blow up in her face.

It has proved to be a Faustian Pact. By next year the interest burden will be 2.7pc.

From there it will ratchet higher every year by mechanical effect. Every item of the US fiscal apparatus – entitlements, interest, and rising defence costs for the new Cold War with the dictators – all paint a portrait of runaway debts.

The US borrows in its own currency and has a modern tax-raising apparatus. It is not about to run out of money like Philip II in 16th century Spain, or Louis XVI in 18th century France.