s2 is a heavy reader and occasionally hosts a book club suggested by members of his Patreon, later posted on his YouTube, and X account.
The books are mostly military history, clandestine stuff, and sometimes material on being a prepared citizen.
To participate and follow along with the current book you will need to join his Patreon.
S2 also has a running list of recommended books on his Goodreads account /s2_actual
Or you can see this pdf of the books he listed as “read” (as of ~ December ’24) here: