If there are communists in Canada and if those communists attack USA, then that's the time for a Canadian to engage in a pincer maneuver.

Watch for hypocrisy (reveal themselves so we know who they are), watch for the crime (entrap with evidence) then charge with crime and punished. So if commies attack from there, their crime is revealed, and highly unlikely anyone is just going to watch that happen.

Freedom and pursuit of happiness is for everyone. People will end up helping the side of right.