NYT: For those blithely inclined toward the view that Britain would somehow find a way to sever its relationship with the European Union free of drama or financial consequences — like canceling a car rental reservation, with a tad more paperwork — Friday was a sobering day of reckoning.

As the British pound plunged some 6 percent against the American dollar in the span of two minutes in early trading in Asia, the markets offered a reminder that divorce tends to be messy, expensive and laced with uncertainties. It rarely ends happily.

The selling was so frenzied and swift that those who swap currencies for a living spoke of computerized transactions going haywire, rogue algorithms at work or a data entry error. The drop in the value of the pound appeared excessive, and it soon recovered some losses, though the British currency was down about 17 percent — around 25 cents — since June 23, the day Britain voted to abandon Europe.

More than anything, though, the precipitous drop seemed to attest to an increasingly unmistakable reality: Britain’s vote to exit the European Union — Brexit, in common parlance — has put its commercial relationships with the world on uncertain and potentially perilous ground. That poses risks for the British economy, making its money less attractive to hold.

“The world believes that the U.K. is going to be poorer in the future, and find it more expensive to trade,” said Paul Johnson, the director of the Institute for Fiscal Studies, an independent research institution in London. “Essentially, the world is betting against the pound.” And against the British economy.