Korea's WTO Case Against China Over THAAD Retaliations?

It has been reported that Korea is considering bringing a WTO case against China over the trade retaliations China has taken in the wake of Korea's decision to install the Terminal High Altitude Area Defense (THAAD) system. However, I think this is unlikely to happen as the Korean government itself is in a major crisis with President Park's impeachment. Moreover, even if Korea does proceed with the case, its likelihood of success would be rather slim as most of the Chinese retaliation measures focus on services and investment, areas where China has made few commitments. Also, China might wish to invoke the security exception to justify its measures. Finally, even if Korea does win the case, implementation will also be a major problem. But, of course, this episode will provide fresh evidence to the theory that trade is related to everything!