Brexit has finally brought down Theresa May

Prime Minister May was supposed to deliver Brexit for the UK. Now she’s leaving it up to somebody else.

Brexit has finally brought down Theresa May.

The British prime minister announced Friday that she plans to resign, after trying — and failing — to steer the United Kingdom through its divorce with the European Union. While this brings a close to her beleaguered premiership, it adds even more chaos to UK politics as the country tries to finalize its exit from the EU.

May will not leave office immediately. She...