http://www.nytimes.com/2016/10/08/world/europe/for-britains-brexit-bunch-the-party-just-ended.html

LONDON — 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. The British pound 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.

The week began with an admission from Britain's new Conservative prime minister, Theresa May, that access to the European market is likely to be a casualty of Britain's pursuit of a primary aspiration expressed in the Brexit vote: imposing limits on immigration.

But Brexiteers had steadfastly maintained the illusion that Britain could have it both ways — that it could retain access to the European market while still controlling immigration. In destroying that idea, the prime minister's admission badly rattled the markets.