In terms of national strategic ties, the Japanese side believed at that time China's reform and opening-up "serves Japan's national interest"; therefore the Japanese government supported China's reform efforts by such means as official development aid. Numerous facts since then have shown through the fast development of bilateral trade between the two countries that China's reform and opening- up in the past 30 years have brought both nations a period of win-win situations.

Apparently China's economy would not have grown so fast nor would the Sino-Japanese economic relations have developed so fast had China maintained a planned economy. This means China was right to pursue reform and opening-up and Japan was right to support them. The two countries supported each other over China's reform and opening-up, which constituted one of the strategic ties between them.

In terms of "sentimental ties between peoples", exchanges of personnel between the two countries' political and business circles and those promoting friendship have increased gradually since the normalization of diplomatic relations between China and Japan in 1972, especially since the beginning of China's reforms. Such exchanges have expanded to the grass-root level, involving large numbers of students, as the frequency of people-to-people exchanges rose sharply.

With a 2,000-year history of friendly exchanges, it felt like old friends meeting again after years of no contact when the two peoples were able to mingle after frozen political ties were thawed. For some Japanese people who witnessed "the terrible things Japan had done in China" with the war of aggression during World War II, their sense of remorse made it particularly necessary to show friendliness toward the Chinese people in time of peace.

In the 1990s, the all-important "national strategic ties" between China and Japan expired when the Cold War ended, while China's fast economic growth and the matching increase of national strength led some Japanese to feel "pressured" or even "threatened". As a result, the voices of support for China's reform and opening-up were gradually drowned by those demanding "containment of China's development".

As for the "sentimental ties between the two peoples", they were overshadowed by a kind of "clash of feelings" as people paid more attention to the other's shortcomings and problems as contacts between the two nations increased.

Meanwhile, the generation of Japanese youths who were born after the war but were never told the truth about it grew up and became elites of the post-war Japanese society. A small number of right-wingers in Japan took advantage of the younger generation's ignorance about that dark chapter in history and went out of their way to deny and distort history, which also hurt the Chinese people's feelings. Years of erosion of the "sentimental ties between the two peoples" finally culminated in the Sino-Japanese political relationship freezing between 2001 and 2006.