Will U.S. Sanctions on Iran Be Effective Without Reinforcement From Allies?

Overnight the U.S. began reimposing sanctions on Iran. These are sanctions that had been lifted when the U.S. was still a participant in the Iran nuclear deal. Now the Trump administration says these renewed sanctions will pressure Iran to renegotiate a broader deal, one concerning its nuclear program and its actions in neighboring countries. But unlike the previous time these sanctions were imposed, the U.S. is going it alone without the support of other countries.