Thought Police - Realistic or futuristic?

The Thought Police in the book 1984 is part of the Ministry of Love, and will constantly be affecting Winston throughout the entire book. The Thought Police is very similar to the Waffen SS during World War 2 in the fact that they monitor each movement done by the people and basically control their lives through fear. When Winston writes in his diary, that act of writing could very well have him condemned by the Thought Police. When Winston writes, "DOWN WITH BIG BROTHER" repeatedly, he says to himself, "The Thought Police would get him just the same" which implies that even if he just thought about it, they could still trace it back to him. When I first read about the Thought Police, it made me wonder if they could really see into peoples thoughts. In the book it says the Thought Police can see what people are doing through the tele-screen, and can also see into people's thoughts. This became clear when Winston said that quote to himself, and it confused me at first.