Two new English words to learn:
Both of these ideologies are part of the driving force of China's attempts at annexing Taiwan as well as its claims to territories of other nations. (A similar thing is driving part of Russia's foreign policy these days.)
What this government in China needs to relearn is that the Manchu Empire was not Chinese. If they want to rebuild the territory of the Manchu Empire, perhaps they should return to wearing the cue and also speaking and writing in the Manchu Language as the language of government.
But China is more greedy than simply reclaiming supposedly lost territory, China demands all of Taiwan, not simply the western half of the island that the Manchu Empire nominally controlled.
We are thankful that Japan is not irredentist or revanchist. But then again, Japan is a free democracy. In this era of history, democracies tend to be peaceful instead of expansionist. The authoritarian dictatorships tend to seek war to seize territory by violence.