Wendy R. Sherman

Opinion columnist

Secretary of State Mike Pompeo started having a tough 2020 only one day into the new year. He was forced to postpone his trip to Kyiv, Ukraine, this week to attend to the new crisis in Iraq. As fraught as Pompeo’s visit to Kyiv was going to be, in the shadow of the impeachment battle, Iraq trumped Kyiv after the New Year’s Eve attack on the U.S. Embassy in Baghdad.

It is President Donald Trump’s failed policy toward Iran that has brought us to this combustible moment.

Iraq is a tough country under any circumstances, made more so after the 2003 U.S. invasion that upended the Middle East and cost so much in U.S. lives and treasure. But Iraq also created strange bedfellows. The U.S. troops worked alongside Iraqi and Iranian militia to destroy a common enemy, the Islamic State terrorism group. And even as Washington was confronting Iran over its nuclear program and malign behavior elsewhere, we maintained an uneasy coexistence in Iraq, where Tehran holds considerable sway.

That uneasy balance was destroyed when Trump withdrew from the Joint Comprehensive Plan of Action, better known as the Iran nuclear deal. Like other critics of the agreement, Trump believed it should have resolved all of America’s issues with Iran. Trump believed we were giving Tehran benefits without a requisite return. He thought a "maximum pressure" campaign would ultimately bring Iran to its knees, or incite a popular uprising against its theocratic regime.

Trump policies devastate US interests

Like much of Trump’s national security and foreign policy, his Iran approach is tactical and not strategic. The results have been devastating to U.S. interests. Iran’s most extreme hard-liners, the Iranian Revolutionary Guards Corps (IRGC) and Quds force, which never wanted the nuclear deal, have gained more power, arguing that the United States couldn’t be trusted to honor any agreement.

Iran’s nefarious activities in the region have increased, because terror is not an expensive undertaking and so is largely immune from economic sanctions. Indeed, the IRGC has happily returned to controlling the lucrative black market under Trump’s sanctions. And Iran, after complying with the deal for nearly three years, now confronted with "maximum pressure" and no diplomatic track, has begun to unwind its compliance.

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In Iraq, Iranian-backed militia, led by Kataeb Hezbollah, have worked to increase their power as the Iraq central government has nearly collapsed under the weight of months of popular protests against government corruption. A rocket attack by the Kataeb Hezbollah militia last Friday killed an American contractor and injured many. The Trump administration retaliated with airstrikes two days later, leading to the New Year's Eve attack on our embassy.

Most would agree that the United States had to respond in some way to the death of an American, but whether the airstrike was the right and proportionate measure is debatable.

Regardless, if the Trump administration really understood the dynamics of Iraq, it might have anticipated a move like the attack on the U.S. Embassy. Administration officials might have worked more closely with the Iraq government to think through the best way forward. Instead, in essence, Trump walked into Iran’s trap.

For many Americans, the Baghdad militia chants of "Death to America" echoed the takeover of the U.S. Embassy in Tehran in 1979, raising the specter of another hostage crisis.

Iran nuclear deal was solid progress

The immediate emergency at our embassy in Baghdad has subsided. Kataeb Hezbollah has withdrawn its militia from outside the compound, declaring that they have delivered the necessary message to America. They want the 5,000 U.S. troops out of Iraq.

Nonetheless, perhaps even Pompeo understands that a longer-term challenge remains, and thus his change of travel plans.

Trump has repeatedly said he wants to withdraw American troops from just about everywhere. But a withdrawal from Iraq at this moment only serves Iran’s desire to exert greater control over Iraq. To much of the world, it would signal U.S. disengagement and weakness — not strength.

Even some of the harshest critics of the Iran nuclear deal now understand that the perfect is, indeed, the enemy of the good; that in volatile international situations, solid, incremental progress trumps chaos. The Iran nuclear deal was meant to prevent Tehran from getting a nuclear weapon. Such a capability would project even greater Iranian power in the Middle East and deter the ability of Washington and its allies to build a lasting peace in the region.

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Concerted action to curtail Iran’s malign behavior, human rights abuses, unlawful detention of Americans and state sponsorship of terrorism remains very necessary. Had Trump stayed in the Iran deal and not only used the remaining sanctions in the U.S. toolbox but also built a coalition of diplomatic partners to challenge Iran to truly join the community of nations, we would be in a very different place today.

Three years into his presidency, Donald Trump owns the events and outcomes in Iraq and Iran, as he does in North Korea, Afghanistan, Venezuela, the Middle East, Russia, China and Hong Kong. Having diminished our State Department, intelligence agencies and military, the very institutions that could have helped him construct an effective national security and foreign policy, he is now on his own.

The president may like it that way, but a change in his secretary of State’s travel plans won’t be enough to save the day, let alone the decade.

Wendy R. Sherman, a professor and the director of the Center for Public Leadership at Harvard Kennedy School, was undersecretary of State for political affairs from 2011-15 and led U.S. negotiations on the Iran nuclear deal. She is a member of USA TODAY's Board of Contributors and the author of “Not for the Faint of Heart: Lessons in Courage, Power and Persistence." Follow her on Twitter: @WendyRSherman