A battle between Detroit carmakers and the United Auto Employees union, which escalated on Friday with focused strikes in three places, is unfolding amid a once-in-a-century technological upheaval that poses big dangers for each the businesses and the union.

The strike has come as the normal automakers make investments billions to develop electrical autos whereas nonetheless making most of their cash from gasoline-driven automobiles. The negotiations will decide the stability of energy between staff and administration, probably for years to come back. That makes the strike as a lot a wrestle for the trade’s future as it’s about wages, advantages and dealing circumstances.

The established carmakers — Common Motors, Ford Motor and Stellantis, which owns Chrysler, Jeep and Ram — are attempting to defend their earnings and their place out there within the face of stiff competitors from Tesla and international automakers. Some executives and analysts have characterised what is occurring within the trade as the most important technological transformation since Henry Ford’s shifting meeting line began up firstly of the twentieth century.

Almost 13,000 U.A.W. staff walked off the job at three crops in Ohio, Michigan and Missouri on Friday after talks between the unions and the businesses in three separate negotiations didn’t end in agreements earlier than a Thursday deadline. Pay is among the greatest sticking factors: The union is demanding a 40 p.c pay enhance over 4 years however the automakers have supplied roughly half as a lot.

However the talks are about greater than pay. Employees are attempting to defend jobs as manufacturing shifts from inside combustion engines to batteries. As a result of they’ve fewer elements, electrical automobiles will be made with fewer staff than gasoline autos. A good end result for the U.A.W. would additionally give the union a robust calling card if, as some anticipate, it then tries to prepare workers at Tesla and different nonunion carmakers like Hyundai, which is planning to fabricate electrical autos at an enormous new manufacturing facility in Georgia.

“The transition to E.V.s is dominating each little bit of this dialogue,” mentioned John Casesa, senior managing director on the funding agency Guggenheim Companions who beforehand headed technique at Ford Motor.

“It is unstated,” Mr. Casesa added. “However actually, it’s all about positioning the union to have a central position within the new electrical trade.”

Underneath strain from authorities officers and altering client demand, Ford, G.M. and Stellantis are investing billions to retool their sprawling operations to construct electrical autos, that are vital to addressing local weather change. However they’re making little if any revenue on these autos whereas Tesla, which dominates electrical automobile gross sales, is worthwhile and rising quick.

Ford mentioned in July that its electrical car enterprise would lose $4.5 billion this yr. If the union bought all of the will increase in pay, pensions and different advantages it’s looking for, the corporate mentioned, its staff’ complete compensation could be twice as a lot as Tesla’s workers.

Union calls for would power Ford to scrap its investments in electrical autos, Jim Farley, the corporate’s chief government, mentioned in an interview on Friday. “We wish to even have a dialog a few sustainable future,” he mentioned, “not one which forces us to decide on between going out of enterprise and rewarding our staff.”

For staff, the most important concern is that electrical autos have far fewer elements than gasoline fashions and can render many roles out of date. Crops that make mufflers, catalytic converters, gasoline injectors and different parts that electrical automobiles don’t want should be overhauled or shut down.

Many new battery and electrical car factories are arising and will make use of staff from the crops which have shut down. However automakers are constructing most aggressively within the South the place labor legal guidelines are tilted in opposition to union organizers, slightly than within the Midwest, the place the U.A.W. has extra clout. One of many union’s calls for is that staff within the new factories be coated by the automakers’ nationwide labor contracts — a requirement that the automakers have mentioned they’ll’t meet as a result of these crops are owned by joint ventures. The union additionally needs to regain the best to strike to dam plant shutdowns.

“We’re on the daybreak of one other industrial revolution and the way in which we’re going is the way in which we went within the final industrial revolution — lots of revenue for a number of and distress and never good jobs for the various,” mentioned Madeline Janis, government director of Jobs to Transfer America, an advocacy group that works intently with the U.A.W. and different unions.

“The U.A.W. is actually taking a stand for communities throughout the nation to verify this transition advantages all people,” Ms. Janis added.

Automakers have been racking up report earnings over the last decade, however they can not afford to lose time from work stoppages of their race to compete with Tesla and international automakers.

The three firms are already struggling to get their electrical car enterprise going. A brand new G.M. battery manufacturing facility in Ohio has been sluggish to supply batteries, delaying electrical variations of the Chevrolet Silverado pickup and different autos. Ford this yr needed to droop manufacturing of its electrical F-150 Lightning in February after a battery caught hearth in one of many pickups that was parked close to the manufacturing facility for a top quality test. And Stellantis received’t even start promoting any absolutely electrical autos in america till subsequent yr.

These issues and Tesla’s rising gross sales might put the union in a robust place to extract a very good deal.

On Thursday, in an indication that automakers are prepared to go a lot additional than that they had beforehand, G.M. supplied a 20 p.c pay elevate over 4 years. That’s half of what the union is looking for however way over staff acquired in current contracts. President Biden on Friday strongly supported the union in remarks on the White Home. The administration has been pouring billions into packages to advertise electrical autos and doesn’t need a strike to delay a centerpiece of its local weather coverage.

Regardless of all the cash that automakers have made in recent times, their executives specific a profound unease concerning the development of electrical autos, which account for 7 p.c of the U.S. new automobile market up to now this yr and are on monitor to surpass gross sales of 1 million this yr. Managers are acutely conscious that conventional firms like theirs have a poor monitor report of retaining dominance after a giant change in expertise. Witness the way in which that Apple sidelined Nokia and Motorola as cellphones turned smartphones.

Auto firm executives and most trade analysts underestimated how rapidly electrical autos would catch on and can’t confidently forecast how gross sales, which have been bumpy currently, will develop sooner or later. “I don’t suppose anybody can completely predict what the adoption will likely be,” Mary T. Barra, the chief government of Common Motors, mentioned in an interview with The New York Occasions final month.

Talking to “CBS Mornings” on Friday, Ms. Barra mentioned an extreme pay elevate would undermine G.M.’s means to proceed producing autos with inside combustion engines whereas additionally creating electrical autos. “This can be a vital juncture the place investing is essential,” she mentioned.

Nonetheless, unions and their supporters are unlikely to precise a lot sympathy for auto executives. Ms. Barra, Mr. Farley of Ford and the chief government of Stellantis, Carlos Tavares, have gotten tens of thousands and thousands of {dollars} in compensation packages in recent times. The businesses’ shareholders have been rewarded with dividends and share buybacks.

Unions “aren’t going to have lots of persistence for sob tales,” mentioned Karl Brauer, government analyst at iSeeCars.com, a web-based market.

Adjusted for inflation, wages for autoworkers in america have fallen 19 p.c since 2008, in response to the Financial Coverage Institute, a left-leaning analysis group.

On the similar time, union officers are conscious of the adjustments within the trade and have mentioned they don’t wish to handicap G.M., Ford and Stellantis as the businesses attempt to get better floor they’ve misplaced to Tesla, which has aggressively resisted makes an attempt to unionize its factories. The Detroit carmakers additionally face challengers like Rivian, a start-up that makes electrical pickup vans and sport utility autos in Illinois, in addition to foreign-owned rivals like Mercedes-Benz and Toyota, whose U.S. factories, principally within the South, aren’t unionized.

“That’s the most important problem right here,” Mr. Brauer added, “attempting to decide to a long-term contract in an trade that could be very unsure and unpredictable over the following 5 years.”

Union supporters say it might be fallacious responsible staff if the normal carmakers can not compete with Tesla and different rivals.

“If you happen to have a look at the breakdown at what it prices to construct an E.V., labor is a really small a part of the equation. Batteries are essentially the most,” Ms. Janis of Jobs to Transfer America mentioned. “This concept that the U.A.W. goes to cost Ford, G.M. and Stellantis out of the market will not be true.”

However different analysts mentioned {that a} lengthy work stoppage might assist Tesla and international automakers acquire floor on G.M., Ford and Stellantis.

“If one thing occurs to disrupt their enterprise, does that give a leg as much as the rising electrical car makers?” mentioned Steve Patton, who abroad the consulting agency EY’s work with auto firms. “Who stands to learn if there’s a protracted strike?”