In a new Upshot column for the 50th anniversary of the Great Society speech, I take on the LBJ mythology that plays a central part in the Green Lantern theory of presidential power:

Lyndon Johnson was not known as a great orator, but 50 years ago today he stood before graduates at the University of Michigan and described his vision of “the Great Society” — a more humane society that “demands an end to poverty and racial injustice.” In his efforts to achieve those goals he enacted programs like Medicare, food stamps and the Voting Rights Act, giving Johnson an image of legislative effectiveness that every president since has been measured against.

On the anniversary of the speech, it’s worth taking a closer look at the Johnson presidency and the frequent comparisons invoked by critics of President Obama and analysts in the press.

The implications of Johnson’s administration for Obama are different from what many of these commentators think. What we perceive as presidential leadership (or lack of it) often reflects structural factors that are largely beyond the control of the chief executive himself — a reality of presidential power that critics of Mr. Obama’s speechmaking and relations with Congress often fail to appreciate.

Read the whole thing for more.