Speculative fiction vs science fiction

Well, the Handmaid's Tale is primarily an example of speculative fiction rather than science fiction. The main distinction in my mind is that science fiction involves inventing technologies or worlds that have not been invented yet. Whereas speculative fiction imagines an alternative world based on current technologies and principles. Thus The Handmaid's Tale, which involves a highly regressive society imbued with no new technologies, is purely speculative of what might happen should an extreme religious group take over the govenment and impose their will. In fact, as shocking as the novel is to Western values, the life it describes is not all that far-fetched from what life in some of the muslim countries is like today.