On ship rudders or airplane wings, there is a component called a trim tab.
By adjusting the angle of the small trim tab attached to the larger surface, the vessel can be held steady or steered by properly balancing the surrounding forces.
Each individual can act as a trim tab to help steer the Vessel of Society.
Buckminster Fuller used the term trim tab metaphorically to illustrate how small, strategic actions can create significant change. Just as a trim tab on a ship or aircraft can adjust the course with minimal effort, individuals or small groups can act as trim tabs within larger systems to influence and steer them in new directions. (Open Civics)