I have seen the U.S. as the repository of mankind’s loftiest hopes and ambitions. But it’s impossible to back Trump’s aggressive trade war against Canada

It is impossible to back President Donald Trump ’s aggressive trade war against Canada , writes Peter Bergen .

Bergen : U.S. is dividing the West , delighting Putin and destroying the electoral prospects of Canadian conservatives.

He says Canada no more provoked Trump 's tariffs than Ukraine provoked Russian President Vladimir Putin 's invasion.