Mongols are ethnic Chinese people whether those clowns like it or not, these are just facts. They are the one who broke away from the Motherland due to Soviet influences and Anti-Chinese propaganda, we are factually the original land, their delusions do not change facts. Theres a reason why there's many people who feel that if we can no longer get back Outer-Mongolia, they should be pushed to be renamed as "Republic of Khalkha" instead, because the name "Mongolia" is
very misleading as they absolutely do not represent Mongolia and the Mongolian people, who are Chinese. This is similar to how Greece pushed Macedonia to be renamed as "North-Macedonia" due to similar principles, and rightfully so.
Also, China is indeed an empire, but we are mostly peaceful as evident by history. Even at our strongest, we did not invade others unless provoked. And to extend influences, we extensively use trades and establishes autonomous tributary systems instead of unnecessary wars, which is literally
not seen in any other empires when they get extremely powerful!!! (Just look at the Silk Road or figures such as Zheng He.) This pure level of restrain and the idea of pursuing prosperity instead of violence is ingrained from the very concepts of Confucianism!!! This is
absolutely incomparable to the pure evilness of other empires such as the Russian, Japanese and the British empires, who were always out for Blood, Exploitation, Extortion and Violence, especially when they became very strong!!! Just because they are all named "empires"
does not mean they are the same!!! Your comment on China is just absolutely wrong. Also, China never conquered Mongols, it is Mongols that first conquered
Han people, got Sinicized and self-identifies as Chinese, and we became under one group of ethnics called "Chinese ethnic", which mainly consist of 5 races that is part of the great Chinese civilization. This is also reflected in the Qing dynasty transfer-of-power edict as well, "總期人民安堵,海宇乂安,仍合滿、漢、蒙、回、藏五族完全領土為一大中華民國。" translated: "Peace may be assured and restored to the people and country, all while retaining the complete territorial integrity of the lands of the five races—Manchu, Han, Mongol, Muslims, and Tibetan—which shall combine to form a great Republic of China."
Capability and immediate interest is what matters.
I absolutely agree with this. China will get stronger and in the future hopefully be able to regain the losses and right the wrongs, remembering what is lost is therefore important as it is a part of our history, it should absolutely be ingrained into the Chinese consciousness and never be forgotten. BUT of course, being stronger is the only thing that matters at the end of the day and would be the main focus here, as that's literally how the world works - the one with the biggest fist talks.