The tenure of Japanese Prime Minister Junichiro Koizumi (2001–2006) was vexing for China-Japan relations. As such, the five years since Koizumi left office, particularly the change in Japan's ruling party, were initially expected, and sometimes perceived, to realize a half-decade of recovery and reconciliation in Sino-Japanese ties. While tensions did decrease, “icebergs” blocking improvement in relations have not completely thawed, and may harden again. Competition for political and economic influences and interests in the same region, concern over one another's future security posture and relations with Taiwan, territorial disputes, misunderstanding about the other's historical sensitivities and feelings of distrust, occasionally manipulated by nationalists, still pervade the relationship. Therefore, though there is mutual desire, indeed a necessity, for cooperation on many issues affecting both countries, this typically couples with a disconcerting or anxious feeling towards the other's intentions that results in competitiveness. There are deep roots to this need/fear complex.