As the U.S. and its allies look to impose even stricter measures against North Korea, leader Kim Jong Un could find inspiration from oppressive regimes of yesteryear in Nazi Germany and Apartheid-era South Africa.
Both managed to survive oil blockades with the help of liquefying coal, a technology that dates back to the 1920s. North Korea has ample reserves of the fuel, at one point leading the world in anthracite coal exports.
U.S. Secretary of State Rex Tillerson raised the prospect of cutting off North Korea's oil supply less than two hours after North Korea fired another missile over Japan on Friday. In a statement, he called on authorities in Beijing and Moscow to take new measures against Kim's regime, noting that China supplies North Korea with most of its oil.