The United States Senate has confirmed CIA director Mike Pompeo, the hawkish former Kansas congressman, as secretary of state. He replaces Rex Tillerson, who was fired via Twitter on March 13.

As a former Middle East analyst at the State Department, I believe that having Pompeo as America’s top diplomat will endanger the Iran nuclear deal.

In 2015, when he was in Congress, Pompeo voted against a multilateral agreement that the Obama administration negotiated to remove some international economic sanctions on Iran. In exchange, Iran would significantly scale back its nuclear program and submit to intrusive international inspections.

Backing out of that agreement could have dramatic foreign policy implications for the entire Mideast region.

Iran deal in danger

Donald Trump tapped Pompeo to replace Tillerson as secretary of state for reasons both personal and political.

The president reportedly found Tillerson arrogant and disrespectful. With Pompeo, on the other hand, Trump reports having very good “chemistry.”

Tillerson earned Trump’s ire by disagreeing with him on many substantive policy matters, perhaps chief among them Iran. Trump has been highly critical of the international nuclear agreement since his 2016 presidential campaign, calling it “the worst deal ever negotiated.”

He wanted to scuttle it when it came up for recertification in July 2017, but Tillerson advised against it on both diplomatic and security grounds.

The former secretary of state was highly critical of Iran, condemning its regional aggression and meddling in the Syrian civil war.

But I believe he understood, as many other policy analysts do, that backing out of the nuclear deal would destabilize the Middle East – and potentially put the world at risk – because Iran would likely react by restarting its nuclear program.

Despite Tillerson’s efforts, in October 2017 Trump finally decertified the Iran deal, which effectively opened the door for the U.S. Congress to reimpose sanctions.

In his January 2018 State of the Union address, he was more direct, calling on lawmakers to “address the fundamental flaws in the terrible Iran nuclear deal.”

Pompeo’s dangerous instincts

Pompeo shares his boss’s dim view.

As a congressman, Pompeo called the Iran nuclear deal – which the Obama administration negotiated alongside the U.K., France, Germany and other key partners – “unconscionable.” After Trump’s 2016 election, he stated that he was looking forward to “rolling it back.”

But during a meeting with French President Emmanuel Macron, Trump recently signaled he might consider salvaging the deal – though he also called it “insane.”

Pompeo likewise moderated his tone during his confirmation hearings, saying that diplomatic efforts to “achieve a better outcome and better deal” could continue after May 12. That is the day that Trump must decide whether to recertify the Iran agreement or allow sanctions to be restored.

Congressional aides who have worked with Pompeo say that he is a smart guy, level-headed and reasonable. But he is also on record saying that Iran is “intent on destroying America.”

The new secretary of state is not the only policy hawk to join Trump’s team in recent weeks. The new national security adviser, John Bolton, has also been a vocal critic of the Iran deal.

If the two of them egg on Trump’s belligerent instincts, I believe the Iran deal won’t last long.

Destabilizing the Mideast

In my opinion, scuttling the agreement could unleash a dangerous chain of events in the volatile Middle East.

If the U.S. reimposes sanctions on Iran, hard-liners there – who have always opposed the nuclear deal – would likely pressure Iranian President Hassan Rouhani to retaliate by restarting the country’s uranium enrichment program.

On April 22, the Iranian foreign minister essentially confirmed this plan, saying his country would begin “resuming at much greater speed our nuclear activities.”

If that happened, I believe Israel would feel justified in taking military action against Iran, which has been threatening its national security for decades. In doing so, Israeli Prime Minister Benjamin Netanyahu would have the behind-the-scenes backing of Saudia Arabia, a regional power and longtime rival of Iran, and possibly other states with a Sunni Muslim majority.

Iran is governed by conservative Shiite Muslim clerics. Sunni-majority countries like Saudi Arabia dislike Iran’s policy of financing violent Shiite militias to push its sectarian agenda in Arab states with significant, and sometimes restive, Shiite populations.

Israel and Saudi Arabia never supported the Iran nuclear deal. They feared that lifting sanctions on Iran would merely give Tehran more resources to foment strife in the Arab world.

Analysts agree that should some Sunni Arab countries team up with Israel against Iran, Iran would not limit itself to responding with missiles. It could also persuade its well-armed allies like Hezbollah and the Palestinian Islamic Jihad to launch rocket attacks on Israel, too.

I doubt Mideast war is the outcome Pompeo and Trump would seek by ending the Iran deal, but it may be just the disaster they create.

This is a revised version of an article originally published on March 14, 2018.

Gregory Aftandilian is a non-resident Fellow at the Arab Center, in Washington, D.C.