Justin Trudeau

Historians in Italy compare Wednesday's events to the rise of fascism. "Violence is incompatible with the exercise of democratic rights and freedoms," Italian Prime Minister Giuseppe Conte said.

The president was reacting to a video that appeared to show the Canadian prime minister and other world leaders discussing Trump, though he is never mentioned by name.

The revelation of the photo comes as Trudeau is launching his reelection bid. "I'm pissed off at myself, I'm disappointed in myself," the prime minister said.

Some point to Canada's immigration system as a model for U.S. reform. Canada is nearly a quarter foreign-born, yet it doesn't seem to wrestle with anti-immigrant nativism that has erupted in the U.S.