Peter Berg is an actor and, for this movie, a director. Another reviewer said that Berg blinked during his last movie (Kingdom) and changed the ending because of the way US audiences like blowing up terrorists. He altered the ending slightly so it wasn't so "jingoistic". Battleship is a collection of "moments" that US audiences will love. The script is weak and the plot is just as weak. In some cases logic has to be very seriously suspended to accept the plot.
On the plus side, those moments are great moments and with fairly good CGI. For the movie watcher you will see some homages to earlier movies. Don't worry about the violence, they're aliens and we can cheer their demise.
I saw this movie during the early morning matinee so it only cost $5. If you can spare the time and money then it is worth it but don't expect to be too impressed.
Liam Neeson was wasted and a number of actors could have phone in the same part.
Rihanna was playing Vasquez from Aliens as has been done a couple of other times.
One person of note was double amputee Colonel Gregory Gadson. His acting is not the best but he is inspiring just by succeeding.