Certainly other nations and cultures in history have conquered, colonized, and spread their ideologies by force. However, European nations launched a big, historically important wave of colonization, starting in the 1400s and ending in the 1900s. There is a specific connection between Europeans and "colonialism." It is rooted in history, and you can find out about it by trying a web search on these terms:
Pope Nicholas V, 1452
Doctrine of Discovery, 1493
I don't know much about Japn's colonization of China.
A lot of it about historically, for instance using the Bible as a source we see that the Egyptians took all the Jews as slaves and later the Babylonians did the same. Chinese literature covers conquests of parts of China by other parts of China etc etc
Basically it is about power and not treating the other country with respect. Of course there can be benefits from that lack of respect. Stopping widow burning in India was one situation where a local institution was destroyed to the benefit of many. But generally it is not a good thing.
@Aliph thank you for the link you shared. There is also a report kept in the National Archives in the USA during the war. Please take a look.
I don't say that nothing happened that soldiers caught women or girls during wartime. There were some cases and it was prohibited in the Japanese military, therefore they were punished by Japanese military court later.The origin of this story came from newspaper articles published in series by one of the biggest Japanese firms, Asahi Shinbun (This has nothing to do with Japanese beer company Asahi :-). The story which Yoshida wrote in the newspaper was/is used as a primary source by supporters of this issue. There are still many people in the world who use this Yoshida's story as a fact, but they ignore the fact that Asahi Shinbun admitted that the article was a fabrication.
I wish that you are tolerant and open to read something totally different from what you learned before.
@Tash try to google neocolonialism , add the word Afrika and China and you will find interesting informations. This kind of colonialism isn’t as brutal as the past ones but insidious.
@Bachir I agree with you colonialism is terrible. But what about neocolonialism? Aren’t developing countries opening their doors to it? Why do countries like yours import foreign (Chinese) workers to build the great mosque of Algiers while thousands of young Algerians are unemployed?