You don't even mention state and local government, where the decisions that affect everyone the most are made! Ancient Athens didn't have a school board, nor a farm extension service. You can go to city or county council meetings and make your voice heard, and meet your representatives. They have to listen to you! You can run for or be appointed to committees that have a lot of say in different elements of city government like zoning, and building codes. I know that leftists like everything centralized, but Washington doesn't run everything, or even most things in this country.

When I lived in Virginia I was on my state delegate's advisory committee, and met regularly with him at a local library with the other committee members. At the begining of every legislative session I went to the Capitol in Richmond and dragged my children along, and we saw the slow grinding of the wheels of government. During the opening session we were recognized by name and applauded by the oldest democratic assembly in the Western Hemisphere. It was deeply humbling.