Donald Trump — champion of Big Labor? Trump might pull off one of the most significant political realignments in modern history, according to Politico’s Rich Yeselson, but perhaps we should make some definitions and distinctions. First, let’s note the moves that Trump has made to encourage labor unions to take a second look at a Republican administration. Here’s Trump this morning discussing his approval of the Dakota Access pipeline, a move Trump says is so popular that he hasn’t had a single complaining phone call about it:

Pres. Trump: 'I haven't had one call' complaining about Dakota pipeline. "I don't even think it was controversial." https://t.co/PINKVVPfov pic.twitter.com/fFfecGxgWH

— ABC News (@ABC) February 8, 2017

Bear this in mind when reading Yeselson’s account of the Trump opening:

Late last month, when President Donald Trump talked with union leaders in the White House, it was something of an unexpected picture: On his first full workday in office, a billionaire Republican president meeting with the heads of major building-trades unions, smiles all around.

For the labor leaders at the table, the news from the White House was encouraging. Trump talked up his proposed infrastructure plan and his executive orders to restart the Keystone XL and Dakota Access pipeline projects. Now, those measures, long trumpeted by the unions present as job-creating steps, were finally nearing fruition. “Today was a great day for America and for American workers,” concluded the statement released by the Building Trades Unions coalition after the meeting.

Many a Republican president has tried to split unions away from their home in the Democratic Party, with mixed and episodic results. Donald Trump might be the first to actually do it more permanently.

Trump might have an opening with private-sector labor unions, certainly, but that’s hardly a surprise. Trump made the “carnage” in the American manufacturing sector his central theme during his presidential run, and he won the election in Rust Belt states hardest hit by globalization. Those efforts were clearly aimed at union workers … or more precisely, former union workers who can no longer ply their trades. His campaign practically did everything but sing, “Look for the Union Label” from the stage.

Because of that meltdown in manufacturing, private-sector unions are a mere shell of their former selves. Most of the historical issues that drove them — wages and working conditions — have been pre-empted by government regulation, and mooted by the collapse of their sector. These unions see free trade as their bête noire, and know that Trump stands outside both mainstream Republican and Democratic circles in opposition to free trade, or at least in skepticism of it. The private-sector unions are just about out of options, so throwing in with Trump is a low-risk trial.

The “unions movement” that Yeselson cites long ago shifted over to the public sector, however, and Trump’s clearly not going to get along with the SEIU and AFSCME. Trump has already angered them over his hiring freeze and his pledge to show thousands of federal bureaucrats the door, which will put a major dent in their collections. Public-employee unions (PEUs) will fight tooth and nail to keep government as big and bureaucratic as possible, and there’s simply no way that Trump’s going to split PEUs away from the party of Big Government, or the party of Big Government away from PEUs. Both of them need the other far too much to separate.

If Trump succeeds in revitalizing American manufacturing, private-sector unions might enjoy a comeback to some extent — perhaps a bit limited by right-to-work legislation that aimed mainly to trim the political sails of PEUs. That at least could provide some competition for political alliances within the overall labor movement, and that would still be an improvement over the last 30-plus years of near-monolithic Democratic support. You have to start somewhere.