With tensions around North Korea starting to make headlines again, in this episode we look at relations between Pyongyang and its closest ally, China.  The North Korean army has already carried out more missile tests this year than ever before, according to the US government - and speculation is mounting that the one-party state may be about to launch its first nuclear missile tests in five years.  Despite their geographical and ideological proximity, China and North Korea have had an up-and-down relationship over the years.  So how are the two countries co-operating now? What do both Beijing and Pyongyang want from their relationship, and how far would China go to defend its ally?  Our guests this week are Tongfi Kim, Research Professor in Asian Geopolitics at the Centre for Security, Diplomacy and Strategy at the Brussels School of Governance; and Jiyoung Ko, Assistant Professor in the Department of Political Science and International Relations at Korea University.