It's been true for a while now that big tentpole movies require of their viewers an enormous amount of what I guess you'd call "extra-textual" knowledge — homework, basically, about whatever "cinematic universe" you're about to enter — but Rise of Skywalker is unique to my knowledge in that it doesn't merely require expansive "in-universe" extra-textual knowledge (of characters, groupings, history) but also "real-world" extra-textual knowledge. If you want to understand this movie — not just if you want to get…