Why are some pro-China government people ignoring USA's contribution to China?

There are many other things the US has done for China. The Hybrid rice that they grow in China came from the US. This enables China to come much closer to being able to feed the people of China. The farm equipment used to work the farms comes from the US. Most all the big farm equipment came from the US along with the new farming methods. The biggest thing the nation of China received from the US was .... We run the Japanese out of China with no help from the CCP. If the US had wanted to they could have fought the Japanese and defeated them leaving China to the beaten Japanese. If the US had done that Russia would own most of China with the remaining parts going to Japan. With no supplies and no air force the CCP would have disappeared. At another point in China's history the Russians told the US they were going to nuke the CCP out of existence, Mao tried to prepare for this. He talked of the nuclear bomb as not the weapon other nations made it out to be but at the same time he built the underground bunker in Beijing. China has much to be thankful for just like all other nations.