South Park: Bigger, Longer & Uncut

South Park: Bigger, Longer & Uncut is a movie starring Trey Parker, Matt Stone, and Mary Kay Bergman. When Stan Marsh and his friends go see an R-rated movie, they start cursing and their parents think that Canada is to blame.
When the four boys see an R-rated movie featuring Canadians Terrance and Philip, they are pronounced "corrupted", and their parents pressure the United States to wage war against Canada.