To President Donald Trump, America's $500 billion trade deficitis a symbol of economic weakness. If he wants a revamped NorthAmerican Free Trade Agreement to shrink that number, he'll need aseismic shift in how cars are made on the continent.

With negotiations expected to start in August, makers ofeverything from toys to microchips are making their case for howthe Trump administration should reshape the 23-year-old tradeaccord with Mexico and Canada. Based on the president's zeal forreducing the deficit, the auto industry could hold the key to U.S.success in the talks. Trump has threatened to walk away from Naftaif he can't get better terms.

The U.S. had a $63-billion trade deficit with Mexico last year,compared with a surplus of $7.7 billion with Canada. The automotivetrade deficit with Mexico was $74 billion. In other words, if youtook out trade in cars and car parts over America's southernborder, the U.S. would actually be running a trade surplus withMexico.