TORONTO — On a recent morning, Francine Piché sat at her desk in a city on the western end of Lake Ontario and began writing a farewell note.
She had already registered her opposition to President Donald Trump’s threats to annex Canada in other ways. Trips to the U.S. were out. So was her Amazon subscription. She found a substitute for her American-made shampoo and checked each item at the grocery store to avoid imports from south of the border.