Epic
It is well documented that Tony Kushner is influenced by his theatrical forefather Bertolt Brecht, who popularized the style of theater known as epic. Angels in America shares many similarities to Brecht's works. The play's action takes place over an extended period of time, and it includes many different settings: New York City, Salt Lake City, a hallucinated Antarctica, the world of dreams, and (in Perestroika) heaven itself.
Also, like Brecht's theater, Kushner's work is socially conscious. When you watch Angels in America, the play asks you to think (and think hard) about the political complexities that make up America. Angels takes it a bit farther, however, delving into the complex conflicting impulses that make up human nature.