Oh, I could not agree with you more, democracy in the US has been and will be predicated on a large enough middle class. Notice I used the word "enough" because you are right that the middle class has been shrinking. About the power of Congress, yes, it has diminished. I do believe though that when sanity returns to both political parties (and it will return, never bet against Americans' ability to eventually snap to common sense), that all branches of government will work on appropriate legislation to restore balance of power.