Prime Minister Theresa May’s retreat on Brexit is best seen as an opening for her former foreign secretary, Boris Johnson, who is the last contender for prime minister to have seen the European Union question clearly from the start. What Mrs. May is doing, after all, is what Mr. Johnson proposed, once it became so clear to so many that she had been snookered in Brussels.

What Mrs. May did in the Commons this afternoon was to announce that she was postponing Tuesday’s vote on the Government’s Withdrawal Agreement bill with the European Union. “While there is broad support for many of the key aspects of the deal,” Mrs. May confessed, “there remains widespread and deep concern.”

The Prime Minister made it clear she comprehends that had she proceeded, “the deal would be rejected by a significant margin.” In the context, it is a breath-taking admission by a leader who’d seemed almost willfully blind on the point. Now, she said, the Government “will therefore defer the vote scheduled for tomorrow and not proceed to divide the House at this time.”

It is easy to see why Mrs. May is vote-shy. Just last week, after all, the government lost three votes. Two were in relation to the legal advice the government had received on the agreement. Parliament had asked for the advice in November but, when only a summary was provided, the Commons demanded the full report.

Mrs. May lost one vote to postpone this vote, then lost the vote itself — a vote that many say was signaling that the Government was in contempt of Parliament.

The third vote is even more momentous. The Commons won a vote to set out its own Brexit “Plan B” if the Government cannot get its plan through Parliament. This could be another Withdrawal Agreement or another referendum vote — even to shelve Brexit unilaterally, as the European Court of Justice announced today in answer to a query from the Scottish legislature and for hopeful Remainers.

Mrs. May told the House she would bring their concerns — still centered on questions in respect of the Irish border — to European leaders later in the week. Never mind the consensus on the continent that they have ended negotiations and that it’s this deal or none.

The eventual vote may take place before the Christmas break or, as it is looking more likely, early in the new year. Some suggest that the Prime Minister will prolong the vote as long as is seemly, staking the outcome on “her Brexit” or “no Brexit.”

Nor does it look like Mrs. May has granted herself a temporary reprieve. Calls for her resignation have only increased and whatever sympathy she may have garnered for her tenacity has largely dissipated. If nothing else, she has succeeded in rallying Leavers and Remainers, Conservative, Labor, and remaining MPs — against her.

It’s anyone’s guess what happens next, but Boris Johnson beckons. Since resigning as Foreign Secretary in July over the Chequers outline of the Withdrawal Agreement, he has been urging Mrs. May to change course and return to the fundamentals of the Brexit promised in her Lancaster House speech.

As the vote for the Government’s plan neared, Mr. Johnson continued to exhort the prime minister, while laying out his own Brexit agenda. Refuse to pay the £39 billion until the EU scraps the idea of an Irish backstop, he says. Work out the border details during the 2-year transition period.

Then, Mr. Johnson offers, only pay the remainder upon achieving a “big and generous zero tariff zero quota free trade deal.”

Let there be no mistake. BoJo has his detractors within his own Conservative Party, let alone Parliament and the nation at large. Surely, though, his continuing optimism, Brexit credentials, and presentation of an alternative Brexit outline, should count for something. Besides, other than Mrs. May, there’s no one else standing in the field of battle. Hasn’t Mr. Johnson earned himself the right to try for the keys of 10 Downing Street and bring home to the British people the Brexit dream they were promised and for which they voted?