Boston Herald | Kimberly Atkins: President Trump�s decision on whether to stay in the Iran nuclear deal, ditch it or push for amendments � which he will announce this afternoon � will have a ripple effect on not only the U.S., but also its allies and the upcoming high-stakes bilateral nuclear talks between the U.S. and North Korea.

His decision will end months of speculation on the pact negotiated during the Obama administration with an aim of curtailing the Iranian nuclear program for 15 years.

But if he follows through on his threat to tear up the deal � something his attorney and former New York Mayor Rudy Giuliani has signaled would happen ��� it would put those who remain under the terms of the deal in a tenuous position of facing potential U.S. sanctions if they maintain economic ties with Iran. It could also throw a wrench into Trump�s upcoming summit with North Korea leader Kim Jong Un.

�The signal it sends is that unfortunately you can�t trust the United States to live up to its commitments,� said Daryl Kimball, executive director of the nonprofit Arms Control Association.

The two world leaders who have been most vocal about opposition to the deal are Trump and his close ally, Israeli Prime Minister Benjamin Netanyahu. Last week Netanyahu held a media event decrying the agreement, saying it has allowed Iran to advance its nuclear capabilities � a message seen as aimed toward Trump as he pondered his decision on the nuclear pact.

Netanyahu has reiterated his view, saying that stopping Iran�s aggression is better done �now than later.�

�Nations that were unprepared to take timely action against murderous aggression paid much heavier prices afterwards,� Netanyahu said before a Cabinet meeting this week.



But unraveling the U.S. from the multilateral agreement � and reimposing U.S. sanctions � will be complicated. Taking the so-called �nuclear option� of reimposing all previous U.S. sanctions against Iran at once would mean that the U.S. would be in violation of the terms of the pact.

A second option of incrementally reimposing sanctions against the country�s central bank would start a 180-day clock for other countries to begin winding down their own oil and other trade with Iran � a move they will have to take to avoid facing their own sanctions from the U.S.

But it could also create a new foreign policy problem for those countries that have expressed no intention of leaving the pact, including U.S. allies Germany, France and the U.K.