Story highlights Trita Parsi: Real flaw in Iran deal is that negotiators never foresaw someone like Trump becoming President of the United States

Trump defines himself by taking the opposite approach to his predecessor on key issues, Parsi says

(CNN) It's still unclear whether Donald Trump's expected decision to decertify the Iran nuclear deal will lead to the total collapse of the agreement. But the truth is that decertification is only half the story. The bigger threat to the deal is Trump's apparent intention to ratchet up pressure in the region on Tehran. Doing so risks not only scuppering the agreement, but putting the United States and Iran on a collision course that could result in outright conflict.

We're only seeing "the calm before the storm," Trump said cryptically last week . Was he talking about North Korea? Or Iran? The uncertainty over the answer to that question goes to the heart of what is really the biggest flaw in this imperfect, but still highly successful, agreement. While many in Washington bemoan it for not having completely eliminated enrichment in Iran (an impossibility) or for not somehow permanently punishing the country (also an impossibility), the real flaw is that negotiators never foresaw someone like Trump becoming President of the United States.

Trita Parsi

Much energy was spent on preventing Iran either cheating or withdrawing from the deal. However, far less energy was put into insulating the deal from a TV reality star turned President whose agenda appears to consist largely of trying to undo the achievements of his predecessor. As a result, despite eight reports by the International Atomic Energy Agency confirming Iran's compliance with the agreement, and despite US intelligence and senior members of the Trump administration stating that Iran is in compliance, it seems likely that Trump will decertify Iran this week, while stopping short of calling on Congress to snap back sanctions.

Some see in this approach a way of salvaging the agreement. They argue that decertification alone is not enough to kill it . Congress could, for example, choose not to reinstate sanctions, leaving Trump with the political benefit of no longer having to certify Iran's compliance, while avoiding an international backlash by killing the deal and running the risk Iran restarts dormant aspects of its nuclear program.

But this analysis misses a key point: It is not only the reinstatement of sanctions that threatens the deal, but the Trump administration's desire to "push back" against Tehran in a way that some senior Pentagon officials believe both Obama and George W. Bush failed to do. If only, the thinking seems to go, the United States were to demonstrate its military superiority -- and willingness to use that might -- in a small confrontation, Tehran would have no choice but to back down.

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