Battleship is the kind of movie you find yourself having to explain why you even want to see it. Based on a boardgame, no-one's going to go into it expecting great characterisation, originality, or anything really beyond things blowing up. Since I like disaster-movie-alien-invasion stories, even if I expect them to be a steaming mess, I just settled back for the inevitable feel-good end, and the sport of picking the scientific idiocies apart.
What I didn't expect was the incredibly tedious first half hour of "establishing characters", particularly the main character, some kind of slacker loser whose encounter with an extremely hot girl (or, uh, the police) is the spur to him joining the navy. [A slacker loser who obviously spends a large portion of his life working out, but we'll pass over that.] Given his ego and temper, it's quite something to swallow that this guy manages to get to the rank of Lieutenant in the US Navy in only a couple of years, but anyway...
After all the boring set up we have some multi-country Navy war games off Hawaii, a main character we don't particularly like, an oh-so-symbolic personal rivalry with a Japanese officer, main character's super hot girlfriend who is a physiotherapist, one of her physiotherapy subjects, an army guy who has lost both his legs and most of his will to live (he would have made an interesting main character!). We've also embedded some earlier back story with a (predictably wimpy, geeky and passive aggressive) scientist who thinks it's a bad idea to send messages to alien planets because the aliens might answer!
I spent some time wondering about a government which would spend untold millions on setting up a wide-orbit satellite and signal system capable of exactly targetting and transmitting to a particular planet, but would not set up any protocol for how to deal with any form of response.
But then, to match this level of organisation, we have aliens who can't drive! The first thing the aliens do after zooming so quickly across the universe that by the time we've noticed they're coming, they're already here, is collide with one of Earth's satellites. Obviously piloted by a reincarnation of the captain of the Titanic.
I spent half of the film trying to figure out what the hell the aliens were trying to achieve. They put up a big dome over Hawaii (and three of the ships which were participating in the exercise) and, uh, destroy a highway and some helicopters? There is actually an explanation, and I quite liked what was the connection to the titular boardgame (though, seriously, why can you pick up transmissions from those things, and not from anything else?), and there were the usual heartwarming moments when underdogs win out. The aliens were a fairly original design when their helmets are off - with their helmets on, you will think this is a movie cross-over with Halo, and the Earth's been invaded by Master Chief.
So, terrible beginning, some cool special effects/alien weapons, a minimal amount of sense, and a striking resemblance to an advertisement for the US Navy. But kinda fun.