An estimated two-thirds or more of North Korea's trade is with China, and the U.S. has repeatedly but ineffectively pressured Beijing to curb Korth Korea's missile tests.
"The reason China has a lot more to fear is that North Korea could collapse," Isaac Stone Fish, senior fellow at Asia Society's Center on U.S.-China Relations.
He pointed out that a failed state would likely result in hundreds of thousands of refugees going into China's economically weak northeast region, while the collapse of North Korea would also likely strengthen the presence of U.S. ally South Korea on the peninsula.
Presumably, a unified Korea would look a lot more like U.S. ally South Korea than like isolated pariah state North Korea.
Meanwhile, North Korean dictator Kim Jong Un appears to have further asserted his control following this week's assassination of his half brother Kim Jong Nam.
Many international observers believe that Kim Jong Nam was under the protection of China as potential leverage against the rogue state's dictator.
"That side of the family seemed to have more of China's interests in mind than Kim Jong Un," Fish said.