Being hunted by one alien killing machine is, admittedly, a lot less badass than being hunted by a whole army of alien killing machines.
When Ellen Ripley (Sigourney Weaver) learns that the planet where she first discovered the Xenomorph is now a fully terraformed colony, she's horrified. When contact with the colony is lost, Ripley knows just how bad it is - but the Colonial Space Marines she accompanies back to LV-426 had no idea.
Trapped in a remote bunker, with the whole alien swarm bearing down on them, Ripley and the Marines had no choice but to - as the age-old adage goes - "nut up, or shut up." And nut up they did indeed. So if you can't admire just how bravely a squad of marines stood in the face of certain death by a horrific enemy, you need to do the backstroke in a volcano just to prove to me that you're tougher.