Jerry Dias wants to hit Donald Trump where it hurts.

If the U.S. follows through on its threat to impose trade tariffs on Canada’s auto sector, the head of Canada’s auto workers union said Canada needs to hit back with restrictions on exports of resources the U.S. can’t live without: oil and water.

“I think we need to get to what really hurts. We’re a nation that’s rich in natural resources and raw materials. The United States depends on us incredibly for our water, our oil, our energy,” Dias, Unifor’s national president, told BNN Bloomberg in an interview outside the Oshawa, Ont. General Motors assembly plant on Thursday.

“I think we need to start retaliating where it hurts them the most.”

The U.S. Commerce Department is holding public hearings on Thursday to discuss the possibility of slapping tariffs on automotive imports.

U.S. President Trump’s administration imposed steel and aluminum tariffs on Canada, Mexico and the European Union in late May. Canada responded with a dollar-for-dollar reciprocal action on a host of goods ranging from whiskey to toilet paper.

“The better path forward is for somebody to talk some sense into this guy, but unfortunately you can’t talk sense into somebody that has none,” Dias said.

“So now, the problem we’ve got is we have to deal with the carnage and we have to retaliate, which sounds so economically foolish, because it is.”

Dias said he believes Trump will move forward with the tariffs regardless of whether it makes economic sense.

“There’s no question he’s going to proceed because, to him, this is all about politics. It’s not about economics,” he said.

But Dias says Trump is blind to the potential fallout in both Canada and the U.S.

“He thinks that’s going to be a political winner, but ultimately it’s only rhetoric because when people start to be handed pink slips and they start to get laid off as a result of his foolish policies, then it’s going to fall like a whole [house] of cards. What he’s doing is problematic for workers on both sides of the border.”

The list of auto industry opponents to the threatened tariffs is vast and includes companies from around the globe including General Motors, Magna International, Hyundai and BMW, among others. Dias believes the automotive companies are not going to bend to Trump’s will.

“The automotive companies are saying to Donald Trump: ‘Don’t do this.’ Because of the integrated industry that we have, it’s going to clobber workers on both sides of the border,” he said.

“Nobody is going to invest, frankly, in Canada or the United States until this is fixed. I know these companies well… They’re not going to say: ‘Okay, you’re putting our industry at risk, so we’re going to reward you.’ It just doesn’t make any sense. I know them well enough to know that they don’t play well in the sandbox.”