WASHINGTON (AP) — President Barack Obama's extraordinary auto industry intervention is assertive and coldly pragmatic, with a dose of caution and a sentimental nod to the automobile's place in the American psyche.

Obama's curt rejection of General Motors' and Chrysler's restructuring plans and his abrupt move to muscle out GM's CEO set the stage for a major realignment of the US auto industry. He bluntly raised the prospect of a "prepackaged bankruptcy" that would reorganise the companies quickly under court protection.

But Obama did not upend Detroit in one single swoop. He gave each company a second chance at a federal bailout — 60 days for GM and 30 for Chrysler — though it was evident that from now on little would remain the same.

"We've reached the end of that road," Obama declared on Monday.

The administration's analysis of the viability of the two auto giants was merciless and remarkably specific in its critique of their business practices. It said GM's underperforming dealers were a drag on the company and its car of the future, the plug-in Chevrolet Volt, held promise but was too expensive. As for Chrysler, the president said it could only survive with an international partner, the Italian carmaker Fiat SpA. All in all, the administration and its auto task force concluded that the automakers' plans to change their mix of products, fix their balance sheets, reduce production capacity and launch new vehicles were simply too slow.

"There seems to be a major difference of opinion between the auto task force and GM not about what's desirable, but what's realistic over some undefined business cycle," Malcolm Salter, a professor emeritus at Harvard Business School who has advised Ford and GM, said in an e-mail.

Yet Obama also conceded the intangible nature of the auto industry as a national symbol, and made it clear he would not let it succumb under his watch. He called the industry an emblem of the American spirit and a pillar of the economy.

"We cannot, and must not, and we will not let our auto industry simply vanish," he said.

The forced ouster of GM CEO Richard Wagoner, the detailed review of the companies' business models and the overt threat of bankruptcy represented an increasingly hands-on approach by the government to institutions receiving federal assistance in the midst of the economic crisis.

But the White House on Monday downplayed the difference between Obama's treatment of the automakers and the less stringent conditions it has placed on the financial industry in return for financial infusions worth billions of dollars.

White House spokesman Robert Gibbs said each institution has distinct effects on the economy and, as a result, the government's response to each would be specific to their circumstances.

On Tuesday, Sen. Bob Corker, a Tennessee Republican whose state is home to auto manufacturing plants, said the administration's aggressive intervention in the industry sets "a very dangerous precedent".

It wasn't just the forced ouster of Wagoner that causes him concern, Corker said on CBS's "The Early Show." He accused the administration of taking a "we know best" attitude in connection with the problems in the domestic industry and said that should "send a chill throughout the country".

The president was hardly ambiguous about his desire to use the beleaguered state of the industry to press one of his top policy agendas — an energy policy that emphasises the manufacture of fuel-efficient, environmentally friendly cars.

"The United States will lead the world in building the next generation of clean cars," he said.

Obama's restructuring conditions include concessions from bondholders, the investors who hold GM and Chrysler debt, as well as from the United Auto Workers, which represents the industry work force. "It will require unions and workers who have already made extraordinarily painful concessions to do more," Obama said.