Iron Triangle diagram.
long description of diagram

Iron Triangles, also called subgovernments, are informal subunits of government built on mutually reinforcing exchange relationships among each triangle's participants. Such mutual back-scratching may promote efficiency and legislative oversight, promote the role of expertise, and protect minorities. But it also may foster backroom deals, favor special interests and the status quo, and circumvent public accountability. Reform of subgovernments requires that the scope of conflict be broadened to include more people, agencies, and interests.