In 1938 Nazi Germany tried to mediate the war between Japan and China. At the time Japanese troops were advancing far into south China, massacring large numbers of Chinese at Nanjing and elsewhere and cruelly seeking to bomb the Nationalist government into submission. If German mediation had succeeded, the history of this part of the world would have been very different.
It failed. Tokyo said that Chinese armed resistance to Japan's advance proved a lack of sincerity for genuine negotiations.
We see a milder version of the same distorted logic in U.S. attitudes toward China today. During the NATO attack on Yugoslavia, China's embassy in Belgrade was hit with pinpoint precision by a U.S. bomb that somehow was able to penetrate an underground chamber where intelligence operations were located. Angry demonstrations against the U.S. Embassy in Beijing coupled with China's refusal to believe the bombing was accidental were then turned round by some in the U.S. to prove that China lacked sincerity, that it was inherently hostile to America.