Speculation or Sci-Fi?

I think the reason Margaret Atwood uses the term "speculative fiction" is because there basically is nothing else that could describe this novel. It is basically a bunch of different concepts wrapped into one book and is hard to categorize into one genre. I don't understand why people feel the need to HAVE to put something into a box. Anyway, I've come to realize that the whole concept of Handmaid's tale can only happen in the future, thus it takes place in the future and then pieces of information are added to fill up the plot to make it seem as if it was the future. Since the future is believed to be more technologically advanced (I mean, of course, we're in the FUTURE.) and so therefore a lot of the elements of the story are added and thus fall under the sci-fi category. She can't write a novel of the past, it's already happened and it would turn into some sort of witchcraft erotica type story as opposed to a dystopian novel. Margaret Atwood added those elements to make it seem as if we were in the future to set up the scenario for this novel.