China and Russia have kicked off their anticipated joint military exercises in the Sea of Japan on Thursday. Chinese state television has described the purpose as ensuring security of "strategic passage at sea". Bloomberg noted of regional reporting that China and Russia are "testing their joint combat capability via the exercise" – but there's been no specification of how long the exercise is expected to last, which involves land, air, and sea military assets. In reality, China and Russia are 'answering' recent US-Japan drills with…