In the 21st century, some argue for deglobalizationfrom a negative perspective on globalization, while others argue that it is re-globalization and that the direction and content of globalization need to be adjusted. As a way to create thinking for new globalization from the latter point of view, this article reviewed the changes and search for sea cities in the region toward globalization in the late 20th century, targeting East Asia and the space of the sea. The reason for paying attention to this region is that the key to the way and content of globalization, which will change in the future, is to realize symbiosis (coexistence) globally. In other words, the meaning of regionalism in East Asia and the network of the people of the sea for the resilience of nature were considered important as an experimental site. As such an example, we looked at the promotion of globalization of Hong Kong and Busan by paying attention to mobility (construction of a new airport), the marine environment, and the residents of the sea. In particular, the construction of a new airport in Busan, the hosting of the expo, and the initiative of the Busan Metropolitan City are all things in the future. Therefore, we pointed out that Busan's change requires efforts to form a maritime network and maritime governance from below that promotes deglobalization, deindustrialization, global solidarity for blue economy, environmental protection, and the resilience of the sea, while considering the issues of re-globalization, eco-friendliness and sustainability. This will serve as a yardstick to gauge whether East Asia and the sea region, which world-class scholars pay attention to, can have a status as a subject and center of concern for the future of the world.