One of the criticisms of the Constitution by the Progressives, and one still heard today, is that the Constitution is so hard to amend that judges have to loosen its restrictions on the power of the federal government by judicial reinterpretations. Judicial activism is one of the enduring legacies of the Progressive era.
In reality, the Constitution was amended four times in eight years during the Progressive era. But facts carried no more weight with crusading Progressives then than they do today.
Theodore Roosevelt interpreted the Constitution to mean that the President of the United States could exercise any powers not explicitly forbidden to him. This stood the 10th Amendment on its head, for that Amendment explicitly gave the federal government only the powers specifically spelled out, and reserved all other powers to the states or to the people.
Woodrow Wilson attacked the Constitution in his writings as an academic before he became president. Once in power, his administration so restricted freedom of speech that this led to landmark Supreme Court decisions restoring that fundamental right.
Whatever the vision or rhetoric of the Progressive era, its practice was a never-ending expansion of the arbitrary powers of the federal government. The problems they created so discredited Progressives that they started calling themselves "liberals" -- and after they discredited themselves again, they went back to calling themselves "Progressives," now that people no longer remembered how Progressives had discredited themselves before.
Barack Obama's rhetoric of "change" is in fact a restoration of discredited ideas that originated a hundred years ago.