There are flights arriving in Canada every single day from the US, India, Ethiopia, China, Mexico, Paris, Switzerland, Portugal, Qatar, England, Morocco, Turkey, Germany...
How is Canada "closed" to all other countries?
Americans have been shoving down our throats for years how great they are, I think it's okay for Canadians to (respectfully) toot their own horn. I happen to think Canada is pretty f*cking awesome and thank my lucky stars I don't live in the US.
However, I can only speak as someone from BC - it might be different in your province