In fact, there was the episode with the merchant marines who tried to start a fight with the service men because they resented the fact their jobs did not qualify for citizenship.
The merchant marines weren’t in Federal Service. Whatever your gig, if you wanted the franchise, it had to be through the Federal Service. As you know, plenty of recruits washed out of MI training. But because they were enlisted as Federal Service personnel, they were sent out to other places for retraining in other fields to serve out their terms.