As the world’s foremost promoter of clean energy and electric vehicles, Musk’s support of an oilman in the role of America’s chief diplomat perhaps seems odd to some. But Musk cited Tillerson’s skills as an executive, rather than his success pulling more fossil fuels out of the ground, as the basis for his support. Commenting on Twitter about a December article in The Economist (paywall), Musk agreed Tillerson “could be one of the more competent members of Donald Trump’s cabinet” (which in some circles, it should be noted, may sound like a backhanded compliment).

Once a climate-change denier, Tillerson said during his Senate confirmation hearings that “the risk of climate change does exist, and the consequences could be serious enough that action should be taken,” distancing himself from Trump’s position. But he fell short of publicly accepting the scientific community’s consensus that there is a human role. In late 2016, Tillerson staked out positions supporting a carbon tax and the Paris agreement on climate change saying in a speech as CEO of ExxonMobil that “the risks of climate change are serious and warrant thoughtful action.”

Tillerson, 64, had been ExxonMobil’s chief executive since 2006 and worked at the oil giant for four decades. Supporters describe him as a tough-minded engineer with small-town Texan values who managed to hammer out deals from Russia to Venezuela, skills that will serve him well at the State Department. White House chief of staff Reince Priebus calls him “a diplomat that happens to be able to drill oil.”

If Tillerson can hold onto Musk’s confidence as he confronts geopolitical issues including the future of energy, he will no doubt cement his reputation for diplomacy.

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