As the national capabilities grew during the early period, the Western Han Dynasty transferred its "hidden light" low-profile policy toward aggressively attacking foreign enemies. It could be considered as a confirmative case to support offensive realism. Some even worry if China would follow the same path today. However, this paper suggests that Han rulers did not necessarily aim at maximizing material power, as offensive realists argue. In contrast, the Western Han peacefully coexisted with weaker Yue people for about ninety years. With the help of the "laissez-faire" ideology, Han elites managed to avoid war. We argue that the Wu Di's war against Hiongnu could be better explained by the concept of security maximization suggested in the defensive realism. Thus, Western Han's case does not fully confirm offensive realism.