One of the hallmarks of a presidential transition in the United States is a comprehensive policy review, aimed at determining which policies to retain and which to eliminate or change. As President-elect Donald Trump moves toward taking office, he seems eager to make plenty of changes — some more positive than others.

Some U.S. policies seem destined not even to receive their day in court. The fate of the 12-country Trans-Pacific Partnership trade agreement seems already to have been sealed, with Trump assuring the public he would shelve that deal — concluded but not ratified by the U.S. Senate — on his first day in office. This is unfortunate, as the TPP would have revolutionized intellectual property rights and boosted transparency to unprecedented levels, while lowering tariff and nontariff barriers. But Trump seems unlikely to reverse course.

In another crucial policy area, however, change by the incoming Trump administration would be welcome: the Middle East. The incremental approach to the region taken by the last two administrations, under George W. Bush and Barack Obama, has meant that the U.S. has failed to keep pace with events.

The Obama administration, in particular, often hesitated to expand its role, anticipating a time when the U.S. would not be absorbed in a region that, to paraphrase Winston Churchill’s line about the Balkans, had produced more history than it has consumed. Nonetheless, Obama understood the value of maintaining a consistent stance in Iraq — something his critics often fail to recognize.

The truth is that it was Bush who, having plunged the U.S. into war in Afghanistan and Iraq, in 2008 signed the Status of Forces Agreement that allotted three years to withdraw all U.S. troops from Iraqi territory. And Iraqi politicians would not agree to postpone that deadline on terms that could be justified to the American people. One can only imagine the reaction of Congress, including those who wanted to keep U.S. troops in Iraq as long as they have been in Germany or Japan, had the Obama administration agreed to Iraqi demands that U.S. troops be subject to the Iraqi judicial system.

All of this left the Obama administration with little choice but to withdraw U.S. forces — and take the associated blame. Indeed, since that withdrawal was completed, the region’s struggles have only escalated, plunging an ever-larger area into conflict.

Trump and his team must think carefully about what has happened in the Middle East and what to do about it. This will require not just an investigation into region-wide challenges, such as Sunni radicalism, but also a careful consideration of bilateral policies.

Start with the continued export of Sunni radicalism from the Arabian Peninsula, a complex issue that involves Saudi Arabia and other Gulf states. While extremist groups have traditionally received funding from the peninsula, it is not sound policy simply to accuse the Saudis of incubating all that is bad in the Middle East, and punish them accordingly. While the U.S. enjoys greater energy self-sufficiency, thanks to shale oil and gas, that is not true of its allies in Europe. Would a tougher position toward Saudi Arabia really be in America’s interest?

Nor is it wise to blame the Shiite — who are, in many ways, the victims — for the onslaught of Sunni radicalism. The tough-minded Iraqi leader Nouri al-Maliki, who won three terms as prime minister, may not have engaged in sufficient outreach to the country’s Sunnis, but that is only one reason why Sunni radicalism persists in Iraq. Another is that some elements of Iraq’s Sunni minority have refused to accept their status as the only Sunnis in the Arab Middle East to live under a Shiite majority.

Then there is Syria, the main flashpoint of the region’s complex social and political dynamics. The civil war there is not just a matter of a ruthless dictator quelling the aspirations of a democratic-minded opposition. Rather, it is a multi-sided conflict, in which identifying the “good guys” is no easy feat.

The Islamic State is, to be sure, public enemy number one, and Trump has already recognized it as such. But how to eliminate the Islamic State not just from Mosul but from the entire world will require a thoughtful, subtle and nuanced approach. Trump’s emerging national security team does not seem to understand this.

Moreover, defeating the Islamic State is just the first step. The Trump administration also will have to deal with the external actors involved in Syria. For example, it will need to devise an effective policy toward Turkey, a NATO member with strong interests in Syria that, at times, conflict with America’s. At a time when Turkish democracy is wobbling, and its leaders are less interested in Euro-Atlanticism than in reasserting century-old claims in the Middle East, the U.S. will, again, need to adopt a tactful approach.

Then there is Iran. Is walking away from the Iran nuclear deal, as many supporters of the new U.S. administration are demanding, conducive to easing the crisis in the Middle East? Iran may not offer much in the way of solutions, but if the U.S. abandons it, the country can easily exacerbate the region’s turmoil.

As if that were not enough, the U.S. also will need to rethink its policy toward Egypt, which, until recently, often made important contributions to diplomatic efforts in the region. Much of Israel’s security is based on an Egypt that supports the peace process with Palestine. As tattered as that process may look, there is still plenty of room for further deterioration.

Trump’s administration has often emphasized its plans to look inward, focusing on domestic policy and putting America first in foreign policy. But Trump will not be able to avoid playing a role in the Middle East. One hopes it is a constructive one.

Christopher R. Hill, a former U.S. assistant secretary of state for East Asia, is the dean of the Korbel School of International Studies at the University of Denver. He also is the author of “ Outpost,” a memoir of his diplomatic service. He is a graduate of Bowdoin College in Brunswick. This piece appears in the BDN courtesy of Copyright: Project Syndicate, 2016.