Presumptive Republican presidential nominee Donald Trump addresses supporters at a rally in Charleston, W.Va., on May 5. (Ricky Carioti/The Washington Post)

ALL THAT wild-eyed talk from Donald Trump about a “total and complete” banning of the world’s 1.6 billion Muslims from setting foot on American soil? Not to worry, folks: It turns out Mr. Trump did not mean it — maybe.

The presumptive Republican presidential nominee, who in December proposed an unequivocal “shutdown” on Muslims entering the United States, even as visitors, has suddenly gone squishy. Mindful, perhaps, of GOP grandees (among others) who regard the idea as loopy, strategically disastrous, an affront to the Constitution and American values, or all of the above, Mr. Trump has lately modified his approach, or at least his rhetoric.

Rather than a blanket prohibition on those who profess a single faith, Mr. Trump and his campaign now propose a ban — temporary, they say, but of indeterminate length — based on a geographic test rather than a religious one. “I don’t want people coming in from the terror countries — you have terror countries!” he said last weekend.

It is possible to guess that he means refugees from Syria and Iraq, for starters, who would have been banned from entering the United States by legislation passed with bipartisan support by the House of Representatives after the terrorist attacks in Paris in the fall. (The bill died in the Senate.)

Yet it is useful to remember that the known Paris assailants were French and Belgium nationals, born and raised there, even though they had visited Syria and at least one posed as a Syrian refu­gee. Would Mr. Trump ban Muslim tourists and immigrants from France and Belgium, or from other U.S. allies, such as Britain, Egypt and Saudi Arabia, all of which have produced citizens who carried out or attempted terrorist attacks?

Mr. Trump’s dwindling ranks of Republican apologists, including New Jersey Gov. Chris Christie and Carl Paladino, a one-time GOP gubernatorial candidate in New York, insist, against the evidence of the candidate’s own words, that he never called for a total ban on Muslims coming to the United States. That risible assertion serves no other purpose than to confirm that his own allies realize that Mr. Trump’s proposal was politically toxic.

The underlying fact is that Mr. Trump suggests different things on different days, according to his whim, or the exertions of his advisers, or the questioner, or his polling numbers. He has said his proposed ban was “just a suggestion”; that “frankly a lot will be banned”; that he would exempt “peaceful Muslims”; and that the ban would be temporary, until a “proven” vetting process was in place. Oh, and meanwhile, Mr. Trump said, he would authorize spying on mosques in the United States, albeit “respectfully.”

The idea of respectful spying on residents and citizens at worship in this country is gibberish, of course — like much of what passes for policy proposals from the Trump campaign. Amid the incessant incoherence, it may be possible to discern a “pivot.” Yet how could any voter believe that today’s pivot won’t be supplanted tomorrow by another?