Present Chinese claim it is a kind of Vanity for the Hans, and it is a kind of lie too.
I do not think all Chineses are Hans.
After Han Dynasty, Central Plains was repeatly repeatly invaded and set up regime by the other nationality. Some other nationalities in order to consolidate the political rights, even make false report, call oneself it for the people in Central Plains. (Example: Tang Dynasty)
Central Plains at the earth, fall over each other, become owner of regime of setting up while being multi-race too, main reason resource abundant, but after they collapse in regime, lose one's own home and land, why Central Plains land ore one is this.
Since state of Qin so far, person in power have a kind of unified more abnormal myth, not only unify one's own nationality or country, even even peripheral race and country will unify.
If there was no help to cover with in 1921 in the kingdom of tsarist Russia the fruit founded the state, it is Chinese that present Chinese must advocate Genghis Khan without restraint, it is the Chinese pride at the same time! (though Mongolia founds the state, when over half of the inherent land is still captured by China)
However, the unified myth coming in thousands of years, let Chinese pay a price, looked for the Hans' blood lineage to China before there are American-European scientists several years ago, appraise through DNA, can not find the Hans' blood lineage on the modern and Chinese body. Can be seen, present Chinese like one heavy to mix, remit, down born mix one kind of nationalities, under the circumstances that the past 2,000 years of this of going through and constant integration of a great deal of nationalities merge again, it is a new nationality!