And on a related point: if you look at an online map of the world and place a rectangular sheet of paper on it so that one of its long edges lies on the equator (alternately covering, for purposes of comparison, the bottom half and the top half), you’ll notice that most of the world’s land masses are in the northern hemisphere. All of North America, all of Europe, virtually all of Asia, and much of Africa are located there. The main land masses in the southern hemisphere are South America, the lower part of Africa, Australia, and Antarctica; the rest of the southern hemisphere is mainly water, which means that for A&A map purposes it’s mostly wasted space. Oceania, a.k.a. the Pacific Islands, including Australia and New Zealand, did see significant action in WWII, so its inclusion on an A&A map is quite relavant…but by the same token Antarctica is a land mass that’s traditionally (and with good reason) omitted from A&A maps.