https://www.tasteofcinema.com/2020/10-vietnam-war-movies-not-set-in-vietnam/2/QuoteOne of the design specifics Cameron insisted upon for the marines was their Vietnam War aesthetic. This included the detail on uniforms, 'Nam aircraft inspired vehicles and gallows-humour graffiti scrawled on armour and weaponry. Cameron even cast a real Vietnam War veteran as the marines' squad sergeant. These details alone don't necessarily make Aliens a Vietnam War movie, but they are a good indication of the director's intentions. What does, however, is having a cocky, technologically-superior military force in a hostile environment underestimating, then losing to, a threat they don't understand – an analogy that preoccupies the rollercoaster action of most of the film.
This is in response to the belief that the Marines were nothing more than glorified pest control.
The U.S. did not consider the same about the Viet Cong and the Viet Minh (the North Vietnamese regulars). That reminds me of a scene from one movie that was released just a year after
Aliens came out, with the squad leader explaining to his newly arrived men why they should respect the enemy and refer to him as "Nathaniel Victor":
(Warning: NSFW due to profanities and racist terms.)
Marines, you will refer to him as 'Xenomorph'. Meet him twice and survive and you will refer to him as "Mr. Xenomorph'." LOL.
Kidding aside, when you look at the weapons that the Marines use (maybe we can go into detail with that in the future) and the tactics that they employ, then you realize that they appear to trained more for than just pest control. I'm not a military expert, but from the movies and TV shows that I've seen (like this old one called
Combat and a newer one called
Tour of Duty), they look like standard maneuvers that vary depending on circumstances. In this case, as they expect a large, armored xenomorph in an enclosed environment, then they send in a point man with a tracking device following by the machine gunner (I think during WW2, the U.S. had someone carrying a BAR), and one for each of the two subgroups that make up the squad (I think in some movies and TV shows, it would be similar to a small platoon, as they had two machine gunners). I think the two groups would sweep the main corridors, then break up into pairs and check each room, and then set up a command post near the lab after making sure that the area is clear.
Given that, it definitely looks like they were not into pest control, but it also looks like they were expecting only one alien and colonists surviving, which is why they didn't set up a CP outside the complex, didn't bring in a medical team, and took up only a fraction of the passenger capacity that the
Sulaco could handle.