So your challenge is to make a nation consisting of the US, Canada, Brazil, Uruguay, Argentina, New Zealand, South Africa, Portugal, Spain, France, Benelux, UK (without NI), Ireland, Iceland, Greenland and Scandanavia as one country. Mexico should be in a relationship with this country that would cause it to be lightly shaded...
I figure it would be easier if Northern Ireland and Australia was included, so that's a fallback...