That noted, as for the type of arms as discussed in the video, some of the choice depends on just what position you choose. If you are part of that slew of people simply going about their lives and keeping your American loyalty quiet, then something small, like a concealed handgun usually kept concealed at home, is sufficient for the weird circumstance when it’s called for — “use it only in emergencies,” ala Mike and the Mechanics (2:22, just one second early!). In addition to purely defense, think of it as a “seed gun” akin to the WWII liberator pistol, and used in a manner again to how the video discusses to obtain serious fire power when the time of deliverance might come.
If, on the other hand, you are seeking a much more active resistance position, the big question is what simply urban versus rural. In an urban setting, something compact like a PDW makes sense. A pistol-caliber carbine holds a certain appeal here, depending on the “intensity” of your intended operations. In a rural setting, particularly if not a trained military veteran or something comparable, I stand by my fudd HDR concept — something akin to a battlefield suitable .308 (keeping in mind the availability issue discussed earlier). It gives you penetration and range, acts as an intermediate between the video’s SPR and precision rifle, though with close-firefight utility, and gives the capability of supporting actual trained personnel as often discussed in this series. Leave the intense fire-and-maneuver to people who know how to do fire-and-maneuver.
TDF INDEX: Cats, Guns, and National Security: THE DAILY FUDD index. https://catsgunsandnationalsecurity.blogspot.com/2021/03/the-daily-fudd-index.html