DONALD TRUMP’S approach to immigration is a practical-minded strategy that holds the promise of defusing an incendiary debate while recognizing political and labor market realities. Donald Trump’s approach to immigration is a humanitarian and economic disaster that will sunder families, upend communities and subvert American workplaces and businesses.

Take your pick. Mr. Trump certainly has. If it’s Wednesday (or Friday, or Monday), it must be pivot day. Demanding consistency of Mr. Trump is like demanding it of the weather — an exercise in la-la-land high-mindedness best left to the sanctimonious precincts of editorial pages.

Yet is it really so pious to expect that a candidate for president might know his own mind with sufficient clarity to present it coherently for the American public? When Mr. Trump outlines his (latest) immigration stance in a speech Wednesday, should voters take it seriously or should they roll their eyes?

To take it seriously invites a stroll down memory-impaired lane. Whatever he says, it’s worth recalling that in recent months or years, Mr. Trump is almost certain to have said very nearly the opposite.

To recap:

●In 2011, Mr. Trump favored a case-by-case review of illegal immigrants – some "great" and "productive" people; others "total disasters" — to determine who should stay and who should go.

●In 2012, he derided Mitt Romney's tone on immigration as "mean-spirited" — the former Massachusetts governor had hoped that illegal immigrants would "self-deport" — saying it probably cost him the presidential election.

●In 2013, he seemed to embrace the Gang of Eight bill then on its way to being passed in the U.S. Senate, tweeting that "amnesty" was fine but "only if the border is secure and illegal immigration has stopped."

●In 2015, he called Mexicans criminals and rapists and promised to build a wall, establish a deportation force, round up all the undocumented immigrants and — well, the rest is history.

And maybe it really is history, as in: Fuhgettaboutit! Because now we learn that, according to Mr. Trump's (latest) campaign manager, his position on a deportation force is "to be determined," as is, well, just about everything else involving his views.

Words matter in politics, but which of Mr. Trump’s words count? He has pandered so extravagantly, flip-flopped so brazenly and now pirouettes so audaciously that to guess his actual intentions, or even pretend that he knows them himself, is a fool’s game. His rhetoric on immigration has been loathsome; it’s been smarmy; it’s been ambiguous. It is formulated episodically, framed for effect, with no purpose beyond attracting votes or, on any given night, cheers.

"There could certainly be a softening" of his immigration position, Mr. Trump told a town hall hosted by Fox News's Sean Hannity last week. Or, he might have added, a hardening. He mentioned leniency for the undocumented 11 million, at least the ones who are law-abiding, if they pay back taxes.

Donald Trump vows to champion immigration reform that would "screen out any who have hostile attitudes toward our country or its principles." (Video: The Washington Post)

Now his policy sounds like Jeb Bush's; now it sounds like President Obama's. Tomorrow it may sound (again) like David Duke's.

Read more:

The Post’s View: Don’t fall for Trump’s pivot toward ‘humane’ immigration policies

Eugene Robinson: Trump ‘pivots’ 360 degrees, back into the mud

Jennifer Rubin: Conway shouldn’t have gone on TV

Greg Sargent: One of Trump’s biggest lies is falling apart. So naturally, he’s blaming the media for it.