“ The manuscript by Xu and Ben-Avraham is a very important contribution to the understanding of the tectonics of the NW Pacific Ocean. The authors have succinctly summarized the key geometrical, kinematic, age relations within the marginal basins of the NW Pacific Ocean. They have proposed a unifying model that links the development of marginal basins in this region. Their model may be controversial in some localities, but their model is testable by future research. ......."