For years now, unions - caring more about gaining power than helping American workers - have joined with business groups to support massive and illegal immigration. So, while this might be news to some, it's more just a recent, ratcheted-up version of something that's been happening for a while:

The U.S. Chamber of Commerce is in discussions with the AFL-CIO and the Service Employees International Union (SEIU) about shared principles for reforming the immigration system, officials involved with the talks told The Hill.

"The cause of the undocumented is our cause, and the Chamber can be a powerful ally in expanding citizenship to all working people in the United States," said Ana Avendano, the AFL-CIO's director of immigration and community action...

Eliseo Medina, SEIU's secretary-treasurer, said he has had serious discussions with the business lobby about what it will take to get legislation through the new Congress.

"What I'm seeing with the Chamber is they have a new energy and have demonstrated much more commitment to this issue than before," Medina said. "Our conservations with the Chamber have not only been about the substance of a bill, but also what action it would take for us to work together to get it passed."

...Both sides want to improve temporary-worker programs. Business wants more access to labor outside the country for jobs that they can't find U.S. workers to fill. Unions, however, have worried that such programs can lead to low wages and poor working conditions for immigrant workers.

"We are looking to come together on joint principles for a depoliticized approach to the labor market in which impartial experts, rather than politicians, determine the future flow of workers," Avendano said...

Apparently Chamber president Tom Donohue and the head of the AFL-CIO Richard Trumka have become buddies, with Donohue saying that he's "working personally with Mr. Trumka, the head of the AFL-CIO, on a number of issues that we can come to some accommodation".

Note in the above that the impact on American workers isn't of concern. Tightening the labor market to assist the millions of unemployed Americans isn't of concern. Resisting Big Business' desire for more cheap foreign labor designed to undercut American workers isn't of concern.

Further Reading

For more on the groups and people involved, see the links above and especially: US Chamber of Commerce, Service Employees International Union, and AFL CIO. Randel Johnson from the Chamber is directly involved in the talks.

What You Can Do

A very ambitious thing you could do about this is to start something like an "American Workers Special Interest Group" inside the AFL-CIO designed to pressure their management to put American interests first.

A much easier thing you can do about this is to point out to those who casually support the SEIU or the AFL-CIO that both unions are joining with those who want to lower wages and degrade working conditions. While labor and bosses have to cooperate, in this case they're colluding to harm American workers. Use that to separate unions from their remaining popular support.