I don't understand why the chinese hate japan this much, are they still holding a grudge for ww2?
I'm sorry if I'm speaking non-sense, it's just that seeing people defending authoritarism makes me furious....
I'm not going to get into the specifics of the Russo-Ukrainian War, as you can make up your own mind on that, but I can speak a little on the Chinese attitude.
Yes, in general and particularly among the older members of the respective populations, China hates Japan. Japan hates China, too. Korea hates both Japan and China. Really, all three of these countries cannot stand each other, which is both hilarious and uneasy given their close proximity. This circle of hatred goes far back beyond World War II, but that is by far the most recent time in which there was so much blood was shed between these states. I feel like us in the West might find ourselves too caught up with what transpired in the Pacific and European theaters, but there's a lot of genuine horror and dismay that manifested over in Asia at the time. It was considered a "world war" for good reason.
China for many, many years had exerted great influence on both the Japanese islands and Korean peninsula, the extent of which scaling from merely the exchange and spread knowledge and policy to complete subjugation. What has ended up happening is that, in recent centuries, Japan and Korea have grown up. They have rapidly industralized and evolved from their more archaic societies of the past, particularly in Japan. They shed much of the influence of their Chinese masters (though, unlike the Koreans, the Japanese so far have failed to evict 漢字 from their language, but that's a rant for another time) and have evolved into modernized, largely democratic technological powers. China is largely stuck as an industralizing, smog-ridden, rice farming state because it has been utterly ravaged by the ill-effects of both an authoritarian regime and communism for over a century. Their "success" as far as economic and militaristic power goes is akin to a marathon runner who wins a race because he's coked up on meth, despite the devastating damage done to his body as a result.
And it really fucking sucks, because I think China used to have a genuinely rich history and it has contributed so much in the way of science, economics, art, and theory over its millenia of existence. The extent to which the communist regime has sucked the life, spirit, and merit out of the Chinese identity is truly devastating, and it should serve as one of the greatest examples of the evils of such a philosophy. However, I'll get back on topic before I digress any further. To conclude this thread in short, the Chinese Mandate of Heaven and its complementary dynastic cycle could very well be legitimate given how the history of the country's power and influence is so cyclical. I have a feeling the wheel may be turning in the near future.
What you're seeing happen between the Japanese and Chinese online is merely a manifestation of the differing philosophies of the two cultures. Many Chinese are overly nationalist, and despite the state-sponsored atheism, they certainly worship their party as if it were a divine entity. They will do whatever their party says, support whatever the party supports, and agree with whatever the party agrees. In this matter, China is buddied up with Russia, and therefore the drones of the party will subsequently say the same. I don't honestly know if these sorts of people are capable of much independent thought, they're just walking proxies for party officials at this point. The Japanese by comparison have no mandate of allegiance made to the Japanese government that leads them to condemn Russia for their actions, they do so through their own perspectives and by having experienced life in a free and democratic state that has not felt the impact of war or authoritarian rule since 1945.
I do want to clarify that not all Chinese are as I've previously said; there are many who are simply born there and caught up in the madness because, given how the CCP operates, you don't exactly want to openly go against the grain. The ones you see defending authoritarianism and attacking the Japanese for speaking against Russia are likely, however, just CCP drones doing as they will always do: spreading propaganda for the glory of the "people's republic".
Apologies for this being as long as it is, but the histories between these two countries (three if you include Korea) is truly fascinating, complex, and intricate. So much more could be said, and much more needs to be learned and understood to get the full extent of the attitudes and perspectives these particular peoples have against each other.