One of President Donald Trump's goals in imposing the highest tariffs this country has seen since before World War II is, he says, to boost domestic manufacturing. On that front, one of Germany's biggest companies may be about to hand him a big win.

The German business newspaper Handlesblatt reported Wednesday that the Audi division of Volkswagen is considering building a new factory in Tennessee that would build as many as 200,000 cars a year — cars that would be exempt from the president's tariffs.

Building the new plant would exempt Audi from the billions per year of revenue lost to tariffs that its U.S. rivals have reported over the past couple of weeks. But new auto plants aren’t cheap — Handelsblatt reported VW could spend billions on this one — and it can take years to dot all of the i’s and cross all of the t's on permits and get the whole thing built and up and running.

In other words, they’d be spending money to save money. In fact, tariffs have changed the math for any automaker wanting to sell in the U.S.

“All the automakers in the United States and Europe and Asia are furiously recalculating the incentives and the cost they’re facing,” said Patrick Anderson, CEO of Anderson Economic Group. 

It might seem like a simple question: Build cars there or build cars here? In reality, it’s super complicated, because the tariffs are super complicated. Build in Japan, the car gets a tariff of 15%. Build here, your imported aluminum and steel get tariffs of 50%. And parts get different tariffs depending on where you get them from.

“For some vehicles now assembled in North America, including assembled in the United States, the tariff impact is actually higher than for vehicles that are imported from Germany or Japan,” Anderson said.

This would work to Audi’s advantage: build cars here, but with European parts that are cheaper, thanks to tariffs, than the parts its U.S. competitors get from Mexico or Canada. On top of that Audi would piggyback on an existing Volkswagen plant. That’s something U.S. competitors can factor into their math too.

“We don’t necessarily function at full capacity within the production facilities that are already here in the U.S.,” said Erin Keating, an executive analyst for Cox Automotive.

That’s what’s behind the General Motors announcement that it would invest $4 billion to increase domestic production.

Another part of the complex math over where to make cars in a world of tariffs actually comes from the Trump administration’s dismantling of regulations around pollution and electric vehicles.

“Removing any fines from emissions is being added to that calculation, potentially offsetting a tariff of an imported product,” said Sam Fiorani with Autoforecast Solutions.

But in general, he said, the auto industry doesn’t move quickly.

“You won’t see an avalanche of new plants in the United States for the auto industry. There are too many vehicles that cannot be affordably built in the United States,” Fiorani said.

What does he predict we will see? More expensive cars.