North Korea's launch of a third nuclear test Monday evening, the first under leader Kim Jong-un, raised the question of how much slack China will give its ally to the east.
"The big question is, where is China's red line?" Georgetown University Director of Asian Studies and former White House Director for Asian Affairs Victor Cha asked on Andrea Mitchell Reports Tuesday. "One hopes that it was crossed this time."
China, the most powerful supporter of the regime in Pyongyang, expressed disapproval over the test. The U.N. Security Council, including China, "strongly condemned" the test Tuesday and is expected to toughen sanctions beyond those already in place. Cha pointed out on Andrea Mitchell Reports that the test occurred while China celebrated the Lunar New Year.
"In my experience at six-party talks, the time that the Chinese got the most emotional was when the North Koreans were doing things [during] this Chinese New Year holiday, which is a big holiday in China," Cha said. " So I imagine they're pretty upset right now. "
China summoned North Korea's ambassador in Beijing to protest, according to the Foreign Ministry.