Tillerson ouster shakes up energy diplomacy

American policy towards Iran and Venezuela will likely grow harsher, injecting more risk into energy markets

Rex Tillerson is out as US secretary of state after being unceremoniously sacked by his boss via Twitter this week. Oil spiked briefly on the news, but quickly reversed on short-term worries over surging US supply and ended the day down. But Tillerson's ouster is likely to be bullish for oil in the months ahead. The former ExxonMobil CEO was both pilloried for his performance leading the State Department, but also seen at home and in foreign capitals as a moderating influence within the Trump administration. His apparent successor Mike Pompeo, who has been heading up the CIA, will bring a harder version of Trump's "America First" philosophy to the diplomatic scene. On Iran, Tillerson had pub