So what's with these military checkpoints we keep coming across in Fallout 4?
They're usually found along the road, but not always. You can find them on barges and other out of the way places.
They really come into their own when you've chosen a faction to side with and the main game quest has been completed.
You often get miscellaneous quests that involve defending the checkpoint, which is manned by members of your selected faction.
Attackers range from other factions to Deathclaws and other denizens of the Commonwealth. At higher levels, these fights can be both very challenging and very lucrative.
This video delves into the whole issue of military checkpoints and what you can expect from them later in the game...