What's unrealistic about Avengers? The US Military isn't technically the ones doing the Chitauri butt-whuppin'. SHIELD, although having all the trappings of a military, aren't part of the US Armed Forces.
I mean, in Transformers, it was humans-- and US Armed Forces, at that-- that helped defeat the Decepticons. In Battleship, it's the US Navy.
But if it's SHIELD, nope, sorry.
PWNADE(TM) - Serve up a glass today! | PWNZER - An act of pwnage so awesome, it's like the victim got hit by a tank.
There are only four Horsemen of the Apocalypse because I choose to walk!