For those of you who don't know this movie takes it's name for the actual "Battle of L.A." An incident which took place in the 1942. A bunch of mysterious lights appeared over Los Angeles and the military fired at them but hit nothing nor was anything fired back, yet it was dubbed the battle of L.A.
Watch this vid from 4:15 to 7:47
Back to the movie: It felt like it was incomplete. It's got good action and cool CGI but a backstory and message were virtually non-existant and the ending was anticlimactic. By comparison War of the Worlds with Tom Cruise was also anticlimactic but at least that movie had a philosophical message: Divine providence in the form of germs and bacteria which protected us. What message does Battle L.A. have??? "keep fighting"? WTF?
Also they should have explained how those hybrid half machine half biological beings came to be.
The movie just has too many things left out. I'll leave it at that...