Yes, I've always figured that the 'system fleets' (mostly SDB's of various sizes, I reckon) probably fall into 'State Guard' category.
For quite a few years the annual 'Military Balance' published by the IISS in the UK always had a notation appended noting that individual states were allowed to form a "militia" but not all had.

------------------------------------------------------------------------------------------------------------------------------------------------

On Monday, August 24, 2020, 03:34:30 PM MST, Jeff Zeitlin <xxxxxx@freelancetraveller.com> wrote:

To complicate things, many states maintain a "State Guard" that is legally
separate from the State's detachments of the National Guard and which
cannot be called into Federal service. Every state is _allowed_ to have
such an organization; all but Montana, Nevada, North Dakota, West Virginia,
and Wyoming have either an active State Guard (by any of several names) or
have had one in the past (but do not presently have an _active_
organization). (See https://en.wikipedia.org/wiki/State_defense_force)

A world's System Defense Force that is _not_ part of (or cannot be co-opted
into) the sector/subsector "Colonial" fleets would be analogous to the
State Guard; one that can be so co-opted by Imperial order is analogous to
state detachments of the National Guard.

On Mon, 24 Aug 2020 00:14:38 +0000 (UTC), Phil Pugliese wrote:

>Things actually started to change way back in the 1st decade of the 20th
>century as a result of the difficulties involved in mobilizing the state
>militia during the Spanish-American War.I believe that was when the term
>'National Guard' was first coined.Despite that, when WWI started the
>National Guard was still somewhat idiosyncratic.I read that some southern
>states still wore grey uniforms, for instance.During WWI there were a
>number of amalgamations (The famous 'Rainbow Div' of Sgt York fame was
>composed of regiments from the N & S that reportedly had fought each other
>face-to-face  TWICE during the US Civil War) & the old regimental #'s
>dating back to the Civil War were replaced.The process continued thru the
>'20's & '30's up to WWII when the 'Guard was again mobilized into federal
>service.After WWII there was a big reorg.The original plan was to make all
>CONUS US Army Corps consist of one active duty Div, one NG Div, & one
>Reserve Div but the conflict in Korea short-circuited that scheme.Still, up
>to the late '60's, full-time NG personnel were still state employees but in
>the late '60's ('68 or '69, I believe) they became permanent, full-time,
>federal civil service employees, GS ratings and all. 

>Even today each state gov commands his own state's 'Guard in peacetime with
>a full time 'Adjutant General' (two stars) directly under him but they
>haven't had unfettered control since sometime after WWII. Several times,
>when desegregation was in full swing, a southern states NG was
>'federalized' (called into federal service).

>p.s. One of my cousins (VietNam vet) was a full-time PA guardsman (retired
>O6), way back when, & one of my nephews is currently full-time in the MS NG
>(O4).

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