Disputed territories in public maps

Maps of the United States frequently leave out territories like Guam, the Virgin Islands, and American Samoa. Puerto Rico sometimes makes it in, but there are times when even Hawaii and Alaska are left out.

So I find maps of Japan to be interesting -- specifically, who the map is for, what it includes, and what it excludes. Take this map of Hokkaido that I saw in the mall, for example. There's the main island, of course, but there are also four smaller islands to the right -- Kunashiri (国後), Etorofu　(択捉), Shikotan (色丹), and Habomai (歯舞). These are not currently administered by Japan; they're controlled by Russia pending a permanent peace treaty to end World War II.

It's interesting that this map would show them, since they're not always included even on Japanese maps. [Source]
As such, it's an assertion that these four islands are not part of the Kuriles, but are part of Hokkaido prefecture, and thus rightfully belong to Japan.

Another thing I check when I see maps of Japanese is whether they include 竹島/독도(獨島)/the Liancourt islands. Those are disputed with Korea; in an unofficial and quiet concession to Korea, I have yet to see a map that includes them.

And like the full range of the Aleutian islands, I hardly ever see the full extent of the Ryukyu islands down to the 尖閣列島/钓鱼岛, which are disputed with China/Taiwan. More often that not, a map will feature merely an inset for Okinawa, and leave it at that. What a map includes -- and what it excludes -- sends a message about what's important to a country. What it thinks is part of "us." It's important to understand those messages.