Abbreviations

Q. I am editing a manuscript of a law book that uses many specialized abbreviations. There is a table of abbreviations, but we have decided to spell out each abbreviation the first time it is used in each chapter, followed by the abbreviation in parentheses. The only question I have is regarding abbreviations for commonly known words. For example, the author lists the United States in the table of abbreviations. To be consistent, I have spelled out United States the first time it is used and followed it with (US). This strikes me as kind of silly, as everyone knows that the US is the United States. Any suggestions?

A. Yes, I agree that explaining abbreviations like “US” is unnecessary. When consistency gets silly, you can rebel.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]