The document is so dowdy and formal it resembles the annual minutes of a society of tax accountants. Its index lists sections on “objectives” and “rules of engagement” and carries an “addendum” that provides recommendations for hotels and parking. On the cover, two words give a clue to the notoriety of the group that produced it: “MAGA” and “WARNING”. That and the date: 5 January 2021, the day before the US Capitol attack. What goes unsaid on the cover and is barely mentioned throughout the 23 pages is that this is the work of one of the most violent political...