Jimmy Carter will go down in American history as "the president who lost Iran," which during his term went from being a major strategic ally of the United States to being the revolutionary Islamic Republic. Barack Obama will be remembered as the president who "lost" Turkey, Lebanon and Egypt, and during whose tenure America's alliances in the Middle East crumbled.
The superficial circumstances are similar. In both cases, a United States in financial crisis and after failed wars loses global influence under a leftist president whose good intentions are interpreted abroad as expressions of weakness. The results are reflected in the fall of regimes that were dependent on their relationship with Washington for survival, or in a change in their orientation, as with Ankara.
America's general weakness clearly affects its friends. But unlike Carter, who preached human rights even when it hurt allies, Obama sat on the fence and exercised caution. He neither embraced despised leaders nor evangelized for political freedom, for fear of undermining stability.