As a current Naval Officer, I can tell you that about 95% of this movie could and would never happen. So, if you are looking for any semblance of an accurate portrayal of the Navy (especially how National Command Center and leadership make decisions and react or pretty much any leader would act), then this is absolutely not for you. However, I like the movie for entertainment! It should be filed under military fiction, but I think Gerard Butler is a great actor and did a good job and that the movie itself is filmed well. Overall, its an entertaining movie, but completely unrealistic.
We watch it on the ship all the time!