Well of course that's Hollywood, if it had been a white president he would have been a real ass. I despise Danny Glover for his politics and raciest comments but he is a good actor.
I thought the movie was pretty good as well, fast paced and a lot of awesome special effects. The actual science referenced is pretty accurate as well, Yellow stone is truly one huge caldera and has blown in the past and will probably do so again in the next 1000 years. I am not sure the shifting of the Magnetic poles would actually result in the seismic upheaval they advocate. Still I liked the ships they had developed. Made sense in a wired Science fiction sort of way.