Tillerson was thought to be one of the members of Trump's innermost circle cautioning against striking North Korea, while Pompeo has taken a hawkish line.
President Donald Trump announced on Tuesday that he would replace Secretary of State Rex Tillerson with CIA Director Mike Pompeo in a move that could shift the balance of power in his inner circle in a dangerously hawkish direction.
Tillerson, during his time as secretary of state, played an important role in defining Trump's emerging foreign policy by acknowledging political realities and giving up on some of the US's more high-minded ideas like human rights advocacy when it gets in the way of strategic goals.
Importantly, Tillerson was reported to be one of the members of Trump's innermost circle cautioning the president against striking North Korea, while Pompeo has taken a hawkish line against Pyongyang.
Pompeo, as head of the CIA, has said that his organization assessed that North Korea didn't just want nuclear weapons to deter a US attack, but to coerce its neighbors, and that it could export nuclear weapons or sensitive technologies to other states.
Rather than petition Trump either way when it comes to military action against North Korea, Pompeo said his role was to simply provide informed options to the president. As secretary of state, Pompeo may move towards advising the president, as Tillerson was seen as pushing back on the idea of a strike.
The most pressing North Korea issue is currently the upcoming May summit between Trump and Kim Jong Un, one in which Pompeo has declared the US will make "no concessions."
"Tillerson’s firing comes at a moment of volatility on both strategic and economic fronts. Tillerson has been a calm and steady voice, especially on North Korea and the Middle East, though often contradicted by presidential tweets," Robert A. Manning, a resident senior fellow in the Atlantic Council’s Scowcroft Center for Strategy and Security said.
"Pompeo has been more alarmist and a bit more hawkish on North Korea than Tillerson, so in regard to the path ahead, the Trump-Kim Jong-un summit and beyond, it may presage a more rocky road," continued Manning.
Should the talks fall through, or play out as a kind of trap to generate positive propaganda for North Korea while laying the blame for the burgeoning nuclear crisis on the US, as some experts fear, Trump's White House will be without one more voice urging against strikes.