Iron Dream is definitely one of the most disturbing SF novels ever written. The introduction sets up an alternate history meta-fiction premise that after WWI Adolph Hitler immigrated to the US and became a Science Fiction writer. The bulk of the text consists of Hitler's Hugo Award winning novel. Spinrad is attempting to highlight the fascist undertones of a lot of militaristic SF, particularly in the work of Robert Heinlein. The book is violent and incoherent and everything you would expect if Hitler had been a novelist. It is an impressive piece of work, but not something you will actually enjoy reading; and if you do find yourself enjoying it then you may need to take a hard look at how you entertain yourself.