President Donald Trump's threats to impose punishing tariffs on Canada and Mexico may be part of a strategy to gain leverage ahead of new negotiations on a regional trade agreement, experts said.

Trump plans 25% tariffs on Canada, Mexico. What will it mean for Iowa's economy, farmers? Last time it left a $2 billion dent

China has strengthened trade with Latin America at the expense of the U.S. But Donald Trump, who threatens to raise tariffs on Mexico, could upend those ties.