The meaning of life, relationships, feminism (and all equality issues for that matter), the environment, politics.
Feminism is basically the stance of women having the same rights as men. They speak out against things like uneven salaries, and sexual predators, etc.
Fiction or Non-Fiction? If you are looking for something that is serious and non-fiction, what about the Ebola virus? Air travel, open/closed borders, people going there to help, whether there are any plans for if a outbreak happened hear, are we safe. http://www.lyricideas.com/index_files/SongThemeIdeas.html I know it's about song topics, but you might find something helpful there.
I don't think most politicians would let that stand in there way.