The letter reiterated Trump’s complaints about dairy quotas, fentanyl and the U.S. trade deficit, which is mostly fueled by American refineries’ thirst for Canadian oil. His social media post caused the Canadian dollar to immediately tumble, indicating the market wasn’t expecting this escalation.

The country’s new prime minister, Mark Carney, has been called the “Trump whisperer,” and negotiations have been cordial and professional. But it’s been a wild ride.

Trump's tariffs have companies scrambling as they navigate cost increases. Here are the companies that have talked about hiking prices.