[Hunpecked]

With regard to the Icaran military only:

Yes, by World War II standards it does seem extremely low in manpower relative to the population, although as El_Phil pointed out there are a lot more people "behind the scenes" supporting the military: R&D, construction, merchant navy (moving resources back and forth), supply, maintenance, etc. that SEIV doesn't explicitly include.

Note that even this minuscule military is probably an overestimate. Given likely advances in 25th Century automation, a crew of 6,000+ for a super dreadnought seems wildly excessive. Personally I don't have a clue what the 25th Century will look like, but I'll bet it includes AI's with REAL "I" and highly advanced robots/droids of some sort, capable of far more than Star Wars-type comic relief.

On the bright side, having a small military means the Navy can recruit the best of the best of the best; probably the lowest swabbie on the ship is an Olympic-class athlete and chess grandmaster with a Ph.D. or three. You won't find this guy swabbing decks, either.