A commenter drew attention to the flag in the window (along with a Kerry-Edwards sign) in this photo (second image) and seemed think it was just a meaningless decorating choice. But the American flagas a window treatment dates back to the hippie era. I'm not sure why it became so easily comprehensible that the flag stood for the anti-war position back then, but the old practice has lived on.
What other flags can be seen in Madison windows? There's this: