How serious would a conflict with North Korea be?

How serious would a conflict with North Korea be?

(BBC News) –China has warned that tensions are so high on the Korean Peninsula that conflict could break out at any time.

Joel S. Wit is a Senior Research Fellow at Columbia University in the US and worked as a US official on North Korean issues in the 1990s. Does he agree that Trump’s strong line on North Korea has produced some movement in China?