An honest one wouldn't, because it's categorically untrue.
"U.S. exports were $441 billion, while imports were $482 billion, resulting in a United States $41 billion trade deficit with Canada."
This doesn't even count the multinational tech corporations providing services in Canada through a local subsidiary, something that is not counted in balance of payments.
But this is probably culture-specific. When Finnish media describes someone as (the Finnish equivalent of) a businessman, he is almost certainly doing some shady stuff and has often also committed crimes. People described as entrepreneurs tend to be more respectable and more likely just doing legitimate business.
But Canada has absolutely tried negotiating. There's been a continuous stream of Canadian politicians visiting DC and trying to talk to someone - anyone. If all the provincial premiers and the minister of foreign affairs show up and the best you can offer is your assistant chief of staff of personnel or whatever, then clearly you weren't in the mood to chat/negotiate.
It's time to stop negotiating and start finding new trading partners is the view of many Canadians.
Meanwhile, the actual stated reason for the tariffs is fentanyl, yet only 1% of it comes from Canada, and even then Canada has agreed to US demands of further securing the border.
Is it about trade deficits? Seems hard to believe, given that the USMCA was negotiated by Trump in 2018, and he hailed it as the "fairest, most balanced, and beneficial trade agreement we have ever signed into law".
Is it about bringing back manufacturing to the US? Then why is China being hit with less trade tariffs than Canada (20% total vs 25%) when the US imports around the same amount from China as from Canada?
And I mean, not because he would be following laws while criminals got ahead. No, he was a fraudster who still managed to loose money.