Well UK is the country that has just passed a porn ban, and wants to pass a new law to monitor all Internet communications in the country. That puts things into perspective for what we used to think about this "modern western country".
US is actually not that far behind from doing this and more - Constitution or not. They'll just pass the laws and deal with it 10-20 years later. After all US still has the Patriot Act, and that never seemed too constitutional to me.
What's funny is that the Eastern Europe countries are probably the least likely to go this path anytime soon, and that's because it wasn't that long ago when they had revolutions over this kind of thing. But UK and US hasn't really done that in a long time, so neither the Governments nor the people there really get what it means to have mass-surveillance and have the Government know everything you did or want to do, and how bad of a thing that truly is.