Tam, at View From The Porch, talks about an important shift in our Constitutional structure:
On April 8th in 1913, the 17th Amendment to the Constitution went into effect. ...In the years since 1913, the effect has become all too obvious. Treaties are ratified based on pressure from the media, not their agreeability to the sovereign states that are bound by them. There is no longer a legislative brake on popular fads or the whim of the moment. We've bounced from New Deal to New Frontier to Great Society to everything short of the Great Leap Forward...this nation became a democracy, for good or ill, with the passage of the Seventeenth Amendment.