After the Cold War, the American self-image became that of the "sole superpower." We were the only 800-pound gorilla in the world, and therefore we could do what we pleased without having to worry about any other country's ability to stop us. Russia, under Putin, is reasserting itself as the second weighty gorilla in the room.
The defeat of AIPAC's ill-advised push for new sanctions on Iran in the midst of successful negotiations is nothing short of historic. The powerful and hawkish pro-Israeli lobby's defeats are rare and seldom public. But in the last year, it has suffered three major public setbacks, of which the sanctions defeat is the most important one.