Well, actually, it is.
There were 1200 years of war, conquest, slavery, ethnic cleansing, genocide and apartheid up until the caliphate was defeated and broken up in 1920/1924. For 1200 years, non-muslims lived under apartheid (Dhimmi). Up until that point, Islamic supremacism was as firmly established as white supremacism was in America.
I suppose if America (which itself was built on war, conquest, slavery, ethnic cleansing, genocide, and apartheid) was defeated in WWI, broken up into various nations, and some land was made available to the Native Americans to build their own sovereign nation, you would be against that ? After all, at that time, Native Americans accounted for only .25% of the population. Since there were so few of them it would make no sense for them to have their own nation.
Wars have consequences. Many ethnic groups lost their lands due to the expansion of the caliphate over 1200 years. The caliphate was then defeated, and things have changed.
"... ethno-centric racism are never good".
While in no way saying that this supports the idea that "ethno-centric racism" is good, you should read the constitutions of the 22 Arab countries in the Arab League. They have, as their basic principals that they are Arab/Muslim countries, and have Islam/Sharia as their law. So, are all of these countries also illegitimate ? Or, just Israel ? Or maybe America should change its constitution to declare that America is a white European country based on Christian law ?