Members of Congress, among others, have raised concerns about Tillerson’s business history in Russia and intimacy with Vladimir Putin. But there’s another region high on the American agenda where Tillerson’s semi-diplomacy has been tested: Iraq and the Kurdistan region. There, in 2011, Exxon secured a controversial oil deal that may inadvertently have lifted Kurdish aspirations for their own state—an outcome the United States and its Iraqi and Turkish allies oppose.

Khedery, an Iraqi American, was the “longest-serving American in Iraq” when he joined Tillerson and Exxon in 2011, having been a special assistant and adviser to several U.S. ambassadors and generals from 2003 to 2010. He stepped away, he said, when it became clear that Washington would continue to back Prime Minister Nouri al-Maliki, who Khedery felt would draw Iraq closer to Iran and govern as “a sectarian dictator who would give life back to al-Qaeda and destroy the results of the surge.”

When Khedery took a job as Exxon’s senior adviser for the Middle East, he said he was surprised to find a culture shaped by risk aversion, in contrast to what he had experienced working for the U.S. government in Iraq—despite the company’s operations in dozens of countries, including sometimes-unstable ones like Nigeria. That culture resulted in part from the fallout over the Exxon-Valdez oil spill in 1989. So when Khedery learned that only months before he started his job the company had signed a $25 billion deal to develop an oil field in southern Iraq, he was worried. “This very risk-averse company was taking a massive risk, potentially $50 billion of risk over the next 30 years in a country that I knew was going to go through hell and was going to become even more anti-American than it was. I said, this doesn’t make sense.”

Instead, Khedery convinced Tillerson to turn to the oil-rich region of Kurdistan in the north, which Western oil companies had been eyeing since the fall of Saddam Hussein. They’d been stymied by the Iraqi government, which was offering bad deals to companies like Exxon to revive the country’s busted up oil fields, many of them in the country’s south. Meanwhile, in 2007, the Kurds approved legislation signaling that that the region was open for hydrocarbon business.

The glaring problem, however, was the government in Baghdad, which had warned companies that they’d be barred from the rich reserves in the country’s south if they did separate deals with the Kurds. According to the Iraqi constitution, the federal government has control of existing oil fields; for new fields under exploration, the regions and provinces would have the authority to develop them. (Revenue distribution is a thornier matter.)

The Iraqi government also feared that any deals with the Kurds, long considered one of the world’s largest stateless ethnic groups, would embolden them in their pursuit of their own state. This was a delicate issue for Washington but, as Tillerson told Rose in 2013, “We do not represent the U.S. government as we travel around the world; we never pretend to do that. And we never ask the U.S. government to do anything on our behalf. We're perfectly willing and prefer to enter countries, construct our contracts and make our negotiations, [between] ExxonMobil [and] the host country.”