Brian Katulis of the Centre for American Progress argues, "It will get rid of an imperfect but effective deal that constrained Iran's actions. . . [but] weakens America's position and leverage."
He contends, "Trump and [Israeli Prime Minister Benjamin] Netanyahu have a similar approach on Iran — heavy on rhetoric and bluster, but light on actual policies that shape the landscape to our countries' advantage."
Ranking member of the Foreign Relations Committee Senator Robert Menendez, D, said in a written statement, "While I strongly opposed the JCPOA, it is a grave mistake to walk away from this deal without a plan for ensuring that Iran does not restart its nuclear weapon programme, without a strategy for countering Iran's dangerous non-nuclear activities, and without our allies and partners."
He added, "The governments of Iran, Russia, and China will seize this opportunity of self-imposed US isolation to continue major weapons sales, deepen economic ties, and further challenge the US and Europe not only in the Middle East but in other areas like North Korea."
The ramifications of this move, taken at a time when Iran is in compliance with the deal, will play out over weeks and months. In the meantime, we should keep our eye on several possible consequences of the deal.
1 Iran is in the catbird's seat
Iran negotiated with the Obama Administration the release of billions of dollars in funds that had been frozen under the sanctions regimen and disabled the international alliance on sanctions.
It has successfully split that alliance and now can do what it pleases with its nuclear programme — either choose to remain in the deal with the Europeans or proceed again with its nuclear weapons programme.
Many will see this as a huge diplomatic win for the embattled regime faced with street protests.
If the fear of Israeli or US military action will, the theory goes, act as a deterrent to a race for the bomb, that same restraint existed before and during the term of the JCPOA.
What the West has jeopardised is an inspection system, far from ideal but better than we have ever had, and a unified front on confronting Iran.
2 Questions over allies' support
Whether US allies will now cooperate with this on non-nuclear matters including sanctions for Iran's ballistic missile programme and its support for terrorism is an open question.
The European Union has every reason to be wary of US promises.
In making it harder to deal with issues that were outside of the JCPOA, Trump makes US overall policy to Iran weaker and less coherent.
3 The Administration's total inability to plan ahead is on full display
Will we exempt allies from newly imposed sanctions? Do we have a military plan if Iran does make a race for the bomb — and if so, will allies join with us after we have backed out of the deal? How will we enforce sanctions?
The plethora of questions belie anti-JCPOA hawks' assurances that the Administration had figured out all the post-deal angles. Hardly.
The Treasury Department advises, "Sanctions will be reimposed subject to certain 90 day and 180 day wind-down periods. At the conclusion of the wind-down periods, the applicable sanctions will come back into full effect."
It's unclear if Trump and his negotiators intend to use this time to extract more concessions from our allies. For now, we lack a clear path forward.
4 It's far from clear what Israel gains from all this
If its intention all along has been to substitute a military solution for the JCPOA, it will find itself isolated internationally and, fairly or not, be blamed for the outbreak of hostilities.
In some respects it has far less room to manoeuver than it did before, in part because conflict with Iran over its deployment of forces in Syria may now trigger a far wider conflict.
Moreover, the Israeli prime minister's role in provoking the end of the JCPOA and any military encounter that follows would severely strain US-Israel relations.
5 Trump and the vast majority of GOP lawmakers who supported this move now own the results
If Iran moves closer to a bomb, if it makes a quick dash for a bomb, if military action ensues, if there is a serious breach with allies or if other non-proliferation efforts are hindered, they will own the results.
The impact on discussions with North Korean talks will unfold, but China may very well give us less assistance and be more skittish about US commitments.
Trump won't have the Iran deal to kick around anymore. Given Democrats' unified opposition here, he will shoulder responsibility for this in a way President George W. Bush never did for the Iraq War (which was widely supported by Democrats).
In sum, we have many more questions today than answers.
What we do see is that a president minimally informed about the world and undoubtedly ignorant about the details of the JCPOA has made a high-risk move to satisfy his own grudge against the Obama regime and to satisfy his base — which you remember was promised an end to involvement in Middle East wars.
Unfortunately, neither he nor his current crew of advisers has the skill or experience to manage the results of their rash move.
