I re-watched The Avengers last weekend and one of my complaints about this otherwise excellent movie is that the alien army seems rather toothless. Sure the dudes are big and scary looking, and they have some kind of energy weapons, but they can apparently be killed with small knives. At one point in the movie, Hawkeye runs out of arrows and easily konks out 3 of the baddies with nothing but his bow. Correct me if I’m wrong, but isn’t Hawkeye is just some normal guy? And aren’t most bows like his made out of lightweight materials like carbon fiber? I don’t think he’d be able to konk out 3 half-trained Marines with M-4s.
The alien army didn’t have any advanced targeting systems (their hit rate is worse than storm troopers). The big flying lizards don’t seem like they’d hold up against a single air to air missile (or the cannon on an A-10, for that matter). The US military is coordinated and has excellent battlefield intelligence. M-16s would be incredibly effective at killing the aliens, and the alien strategy of “drop in from the sky and smash things in an unorganized manner” wouldn’t work very well against the US Army.
In fact, the only thing the aliens had going for them was the element of surprise, but that’s mostly because Nick Fury was wasting all of his time prepping The Avengers instead of being responsibile and letting the joint chiefs do their job.