can a canadian company enforce a non compete in the USA on a independent contractor?

I quit my position as a 1099 contractor with a large Canadian auto dealer sales event company that does business in Canada and the US. I am a US citizen and live in Washington State and do not work in Canada. I started my own company and have a completely different model (I don't sell the same services that my former company does) They now have dug up a packet that includes a non compete clause. I'm not even an employee and did not know I signed a non compete. I was hired in Feb 2012 and they had us sign these packets in Sept of 2012 at a sales meeting. The non compete states that I can not compete in the whole USA and Canada! The agreement was signed in 9/2012 and says it is a one year agreement that automatically renews year after year if not contested??? Can this be enforced? Can a Canadian company stop a US citizen from working in his own country? Especially a 1099 independent contractor?? Thanks, David