The United Auto Workers (UAW) has entered the fourth day of a historic strike that affects Detroit's Big Three carmakers at the same time for the first time ever.

The UAW resumed talks with GM, Stellantis, and Ford starting September 17, but about 12,700 UAW workers remain on strike at three US assembly plants – one at each of the Detroit 3 automakers.

While the strike has nothing to do with Tesla (at least not directly), UAW President Shawn Fein had some harsh words for the EV maker and its CEO, Elon Musk, during a recent broadcast of CBS' Face the Nation that you can watch in the video embedded above (Fein's remarks start from the 10:27 minute mark).

Since Tesla does not use unionized labor at any of its plants, its US facilities are operating normally at the moment. Obviously, this gives the company an advantage, as does the fact that the Detroit 3 would have to increase their labor costs massively if they caved in to UAW's demands.

Ford, for example, said the UAW's demands would more than double its labor costs, which are already significantly higher than those of Tesla, Toyota, and other foreign automakers that don't use union labor. In response, Fein said that labor costs are only a very small part of a vehicle's price.

Gallery: Tesla Giga Texas (Tesla Gigafactory 5)

"First off, labor costs are about 5 percent of the cost of the vehicle. They could double our wages and not raise the price of the vehicles and still make billions in profits. It's a choice. And the fact that they want to compare it to how — how pitiful Tesla pays their workers and other companies pay their workers, that's what this whole argument's about," he said. 

He added that most of the workers in companies like Tesla "are scraping to get by so that greedy CEOs and greedy people like Elon Musk can build more rocket ships and shoot themselves in outer space," which is something he called "unacceptable."

Representative Debbie Dingell (D), who was also on the show, called out Tesla as well for the "huge discrepancy" in what the EV maker is paying its employees.

"Tesla does have a huge discrepancy in what they're paying their employees. And most people in this country can't afford a Tesla. Even a lot of executives can't afford to buy a Tesla," the representative said.

Tesla remains the only major American auto manufacturer not represented by a union in the US. The United Auto Workers and Workers United trade unions have sought to unionize Tesla's workers in California and New York, respectively, but CEO Elon Musk has thwarted all attempts so far.

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