“A DIPLOMAT that happens to be able to drill oil.” That is how Reince Priebus, Donald Trump’s incoming chief of staff, described Rex Tillerson, the boss of ExxonMobil, who was nominated this week as America’s next secretary of state. In fact, Mr Tillerson, 64, is an oil driller through and through, has spent 41 years furthering the ambitions of one of the world’s largest companies, and has sometimes sidelined the American government because he felt ExxonMobil was better able to look after world affairs itself.

Yet Mr Tillerson also has a reputation for dependability and small-town Texan values that has enabled him to stand up to, and win respect from, some notoriously slippery world leaders. Making someone with no experience of government service secretary of state is a risk. But unusual is better than incompetent. Depending on what his confirmation hearings reveal about his views on Russia when not serving Exxon’s shareholders, and assuming he severs his financial ties to the company, Mr Tillerson could be one of just two or three members of Mr Trump’s cabinet whom it is possible to see serving in a normal administration.

For a leader of the world’s corporate elite, Mr Tillerson has parochial roots. Born in Wichita Falls, Texas, he grew up as a Boy Scout, went to the University of Texas, and rides horses in a cowboy hat in his spare time. He has worked at ExxonMobil since 1975, never lived for long outside America, and speaks with a drawl. Jack Randall, a friend from university who is also an oil-industry veteran, recounts how Mr Tillerson still spends time after work fixing up the decking on his lakeside home, despite having numerous employees who would do it for him. “He’s a regular guy who has lived the American dream,” he says. “He’s a Texan, an engineer and a Boy Scout. That is where his values come from.”

Yet as an oilman and ExxonMobil’s chief executive since 2006, he has run operations in some of the most inhospitable parts of the world, from ice-encrusted Sakhalin in the Russian Far East, to poverty-stricken Chad. That has meant dealing with populist strongmen, from Vladimir Putin to Venezuela’s late leader Hugo Chávez, without bargaining away his principles on the importance of markets and the sanctity of oil contracts.

In a book on ExxonMobil, “Private Empire”, Steve Coll recounts Mr Tillerson’s early dealings with Mr Putin during efforts to rein in an unruly Russian partner, Rosneft, on the Sakhalin development. When Mr Putin offered to write an executive order pushing ahead with the project, Mr Tillerson refused, saying that the Russian president lacked the legal authority to live up to his company’s standards. Though Mr Putin “blew his stack”, he gave in to Mr Tillerson’s demands.

In a later oil era, in 2011, ExxonMobil and Rosneft struck a deal to develop oil in Russia’s Kara Sea, which Mr Putin said could lead to a whopping $500bn of Arctic co-developments. In 2013 Mr Putin awarded Mr Tillerson Russia’s Order of Friendship. The Arctic deal was scuppered because of American sanctions against Russia, following its annexation of Crimea in 2014, which were opposed by Mr Tillerson. James Henderson, an expert on Russian oil at the Oxford Institute for Energy Studies, says the Kremlin came to respect ExxonMobil under Mr Tillerson because, although it was uncompromising about ensuring all deals were above board, it was also “dependable”.

Mr Tillerson’s ties to Mr Putin are likely to complicate his confirmation hearings, especially after Russian hackers interfered with America’s presidential election to help Mr Trump. But decades of business in the country mean he is almost bound to understand the way it works better than some of his predecessors at the State Department. Moreover, his defenders are adamant about his integrity. “The chances are better that Mother Teresa was stealing money from her charity than Rex Tillerson will do anything with Putin that is not in the best interests of the United States,” says Mr Randall, the friend from college.

What is less clear is how he will deal with America’s traditional allies, such as Europe, who fear Russian meddling in Ukraine, for example. His appointment will rekindle suspicions that American diplomacy is about securing oil and other scarce resources. NGOs allege that ExxonMobil has a poor record of promoting human rights in countries where it operates, and has flip-flopped on climate change.

Yet as well as having an oilman’s resource-hungry mindset, he could also bring useful industry traits to the State Department and to a Trump presidency. Finding and drilling oil requires elaborate modelling—both of underground geologies and messy aboveground geopolitics—to make money over the long-term. Reputedly his engineering background makes him a stickler for evidence-based decision-making. He is also considered “patient and unemotional” on ExxonMobil’s side of the negotiating table.

Such traits would make him very different from Mr Trump, who lives by the gut. “Rex is not a guy who wets his finger and puts it up in the air to see which way the wind is blowing, and he’ll tell Mr Trump what he thinks,” Mr Randall says. In some respects his opinions differ from Mr Trump, too. Though once a climate-change denier, he now believes mankind has helped cause global warming. This year ExxonMobil applauded the Paris agreement on climate change. In the past he has strongly rebuffed calls (recently supported by Mr Trump) to make America energy independent. With luck, he will not only have the tactical skills to further America’s interests abroad. He will also have the integrity to talk sense into his boss.