In the 1930s progressive liberals in the Roosevelt administration and Congress allied with new mass political forces to build the Democratic order. They led the way in forming a Democratic political bloc whose elements cut across conventional institutional boundaries and whose themes reshaped American liberalism. The new order entailed an expanding state, a renovated Democratic Party, and new movements and interest groups, most notably the labor movement. It was committed to modernization, efficiency, and moderately egalitarian social and economic reform.

The events and outcomes of the decade are still the subject of lively debates, which are often linked to contemporary political positions. For some, the 1930s (and 1940s) show a healthy politics of interest-aggregating parties. Others argue that a special chance was lost to develop a more aggressively reformist liberalism, perhaps a mass social democratic force. Arguments persist about the labor movement and the decade's radical political movements, as well as about New Deal agricultural policies and racial practices.