Every time I see this map (which, AFAIK, is a visualization by the ACLU and not based on an official government publication) I wonder why Chicago and the coastl

Every time I see this map (which, AFAIK, is a visualization by the ACLU and not based on an official government publication) I wonder why Chicago and the coastline of Lake Michigan is included. The border with Canada runs diagonally down the length of Lake Superior, clears the Straits of Mackinac by at least 40 miles, and then continues southeast along Lake Huron to Sarnia and Detroit. The entirety of Lake Michigan is within the borders of the US, so while this entire "100-mile border zone" business is bizarre enough as it is, it's truly disingenuous to include the lower Lake Michigan coastline. It makes me wonder if this is an interpretational liberty taken solely by the ACLU, or if the government's demonstrated behavior truly justifies what is shown on the map.