Mr. Kwarteng, who studied the history of financial crises as a doctoral student at Cambridge University, brushed off the blowback in financial markets as a temporary phenomenon. Like Ms. Truss, he is a believer in disruptive change. Together, they were among the authors of “Britannia Unchained,” a manifesto for a Thatcher-style, free-market revolution in post-Brexit Britain. Among other things, the authors described Britons as “among the worst idlers in the world.”
When, or even whether, Britain can fully recover from this period of political and economic turbulence is not yet clear. On Thursday, as news of Ms. Truss’s resignation broke, the pound rose against the dollar and yields on British government bonds fell.
Virtually all the government’s planned tax cuts have been reversed, and the next prime minister, regardless of his or her politics, will have little choice but to pursue a policy of spending cuts and strict fiscal discipline. Some fear a return to the bleak austerity of Prime Minister David Cameron in the years after the 2008 financial crisis.
“Rishi or another can steady the ship and calm the markets,” Professor Portes said, referring to Rishi Sunak, a former chancellor who ran unsuccessfully against Ms. Truss and may seek to succeed her. “But it’s hard to see how, given the state of the Conservatives, any Tory prime minister can repair the longer-term damage.”
Much of that damage is to Britain’s once-sterling reputation in the markets. Economists have begun mentioning Britain in the same breath as fiscally wayward countries like Italy and Greece. Lawrence H. Summers, the former U.S. Treasury secretary, told Bloomberg News, “It makes me very sorry to say, but I think the U.K. is behaving a bit like an emerging market turning itself into a submerging market.”
That is a humbling comedown for a country that in 2009 announced a $1.1 trillion emergency fund to bail out the global economy.