Date the war
A globe, or a flat map, of the sourced record since 1900, growing by a daily job. Pick the day you think a world war began and see what that dating makes you include.
A black-and-white globe with every sourced event since 1900, a timeline you can narrow to a day, a month or a year and play forward, seven impact groups, a mobilization layer that shows what a war economy looks like before anyone calls it one, and a stress layer for food, water, oil, people and the movements between them. The page never declares a third world war. It hands you the marker.