Americans are not so much linguistically arrogant as isolated. You can go from coast to coast in the U.S. and find English spoken everywhere. In Europe, you can't go very far speaking one language. Of course, this will be true soon in the U.S. as well. In some U.S. schools, kids have a chance to learn Japanese, Chinese, and Italian along with French and Spanish. Maybe this is a sign that linguistic arrogance is on its way out.