Japan, with its financial and high-tech resources, is a foundation participant with the US in the northwest Pacific SeaWeb branch. South Korea works with the US in a smaller branch network, which can be conceptualised as part of South Korea's Kill Chain strategy and infrastructure.
Major targets for the US, Japan and South Korea are Russian, Chinese and North Korean submarines. SeaWeb is being fine-tuned with more sensitive sensors to track enemy UUVs (smaller, quieter than subs and having the advantage of being expendable).
Third Offset Concept
Also see this fine Australian discussion of "The third offset".
So, depending on your interests, Third Offset Strategy or SeaWeb has the most resonance.