Bracing for impact: 5 things to watch with Trump's upcoming tariffs

Countries around the world are bracing for an economic bruising on Monday. And few have more at stake than Canada.

That's because three-quarters of everything Canada sells into the world, it sells to the United States, and U.S. president-elect Donald Trump is threatening trade penalties the day he takes office.

We do know he's planning 100 executive orders starting on inauguration day, and it's virtually certain they will include trade and border measures.

What we don't know is the scope, the severity and the structure of his promised trade actions. Even Trump's Republican allies on Capitol Hill aren't certain, and public comments suggest the full plan won't be complete Monday.

"In a nutshell. what I'm hearing is: 'We don't know what he's going to do,'" Canada's U.S. Ambassador Kirsten Hillman told CBC News, describing her conversations with Republican lawmakers and state governors.

"I'd like to say we know what's going to happen. I suspect we won't know until Monday," she said.

Here are five things to watch.

The president has different powers to implement tariffs under U.S. trade laws. No president in modern history has used these laws as aggressively as Trump is threatening.

Trump will apply different tools at different times, on different countries and products, Canada-U.S. trade expert Laura Dawson predicts.

"I think he's going to try all avenues," Dawson said.

Those potential tools include Section 232 of the 1962 Trade Expansion Act, which allows tariffs on national-security grounds, as Trump once did with steel and aluminum.

Then there's Section 301 of the 1974 Trade Act — it lets a president penalize unfair practices, as Trump and President Joe Biden have both done with China.

Another piece of the 1974 law, Section 122, allows tariffs to alleviate a trade imbalance. It's worth noting here that Trump constantly complains about imbalanced trade.

Finally, there's a never-before-used tariff weapon: the 1977 International Emergency Economic Powers Act (IEEPA), in the event of a national emergency.