White people can be racist against white skin people cause the concept of race is social construct designed by oppressors to colonize and oppress anyone.

Ireland was colonized by the British since the early 12th century. Irish people have faced inherent power systems that was only in favor of the British.

“Whiteness emerged in the colonial period,” she notes. “Before that there were Normans and Saxons and Irish, and various assorted people, but there weren’t whites as such.”

In what way does whiteness influence our thinking? “Everywhere European colonialism happened – and it happened in Ireland too – there were certain ideas, concepts and categories that got sent out to the world. There was a ranking of peoples, and part of the idea of colonialism was that European peoples were the vanguard of the human race: scientifically, technologically, aesthetically, morally, philosophically, politically.

“Whiteness is a historical formation. You can talk about the Irish experience in very particular terms because they were coming in to the labour market at the lowest of the low. They weren’t included in the club of whiteness in the beginning, but have had a particular experience in colonial migration and the labour market because they were at least seen as European, and so were able to make the shift that I think is harder for African-Americans today or people from Latin America or Asia.”

https://www.irishtimes.com/culture/unthinkable-are-irish-people-becoming-less-black-1.2453237

Or how Eastern Europeans faced violence during Brexit.

One of the most concerning aspects of the study was the reports from the young people on the increasing levels of racism and xenophobia in their neighbourhoods since the Brexit Referendum. This had changed the way they felt about their neighbourhoods and the UK- and was a trigger point for some to think about moving, perhaps to another country. Half of the young people in the study said they have seen more racism and discrimination since the Brexit vote and over 75% said they experienced personal attacks, from verbal abuse, being told to ‘go back’ to their country or being called names, such as ‘terrorist’, ‘prostitute’ or ‘bin scrappers’.

For young people who think of Britain as their home, these experiences are deeply distressing - many told about the disruption to their sense of identity, like Arthur: “I moved here when I was six years old, and even though I speak English with a British accent, as a result of using the language for over 11 years, when people find out I am Polish, I often face racism and discrimination. I find that I belong as long as no one finds out y nationality.”

The rise in hate crime rates was put at 41% by a Home Office report in the year immediately after the Brexit vote, with 5468 incidents recorded. This is likely the tip of the iceberg- young people said they do not normally report incidents, as teachers or police would not treat these incidents seriously- possibly because they are white. As over 500 young people, half of the participants, described incidents they were victims of or they witnessed, the evidence shows that being white is not a protective factor for young people from migrant background living in post-Brexit Britain. To protect themselves, young people said they started avoiding speaking their home language in public, learnt to put on a local accent or tried to ‘blend in’ through the clothes they wore or their appearance. Fears of discrimination and attacks leads young people to deny who they are and their multicultural identity.

https://www.huffingtonpost.co.uk/entry/eastern-europe-brexit_uk_5accc2f5e4b0152082fdd6c8?ec_carp=7211846813776112354

Nigel Farage's very racist Reform Party has a legitimate shot at forming the next UK government. Nigel Farage has gone on the record displaying their hatred for Eastern Europeans.

Farage made his bold claim during a Wednesday morning broadcast, questioning host Nick Ferrari directly. 'If I said to you that swans were being eaten in Royal Parks in this country, that carp were being taken out of ponds and eaten in this country by people who come from cultures that have a different... would you agree it happened, is happening here?'

He later clarified his belief that the alleged perpetrators were Eastern Europeans from nations where such practices might be culturally acceptable. The Reform UK leader framed the incident as evidence of broader cultural clashes brought on by mass migration, a theme central to his party's 2025 platform.

https://www.msn.com/en-gb/news/uknews/nigel-farage-caught-saying-eastern-europeans-are-eating-our-swans-in-royal-parks-what-did-he-mean/ar-AA1NguYf

Which the hateful allegation of eating swans and carps is the same thing as JD Vance claiming that Haitians are eating cats and dogs.

Or how about Untermensch was a slur to mean to anyone of Eastern European descent.

It was mainly used against "the masses from the East", that is Jews, Roma, and Slavs (mainly ethnic Poles, Belarusians, Czechs, Ukrainians, Russians and Serbs).

https://en.wikipedia.org/wiki/Untermensch

The Aryan master race conceived by Adolf Hitler and the other Nazis graded humans on a scale of pure Aryans to non-Aryans (who were viewed as subhumans).[10] At the top of the scale of pure Aryans were Nordic-type Germans and other Nordic-Aryan Germanic and Northern European peoples, including the Dutch, Scandinavians, and the English.[10] Latins were held to be somewhat inferior, but were tolerated; and the French were thought to have a suitable admixture of Germanic blood.

https://en.wikipedia.org/wiki/Racial_policy_of_Nazi_Germany

Or Finnish people in immigrant to the US.

Acrimony toward Finnish social radicals in Minnesota's political milieu reached a head in the case of John Svan and 15 associates. On January 4, 1908, a trial was held regarding whether John Svan, a socialist, and several other Finnish immigrants would become naturalized United States citizens or not, as the process only was for "whites" and "blacks" in general and district prosecutor John Sweet maintained that Finnish immigrants were Mongols. Sweet linked the "socialistic ideology" of Finnish radicals with other collectivist East Asian philosophies to underscore his position that Finns were of an Asiatic frame of mind that was out of harmony with American thought. The judge, William Alexander Cant, later concluded that the Finnish people may have been Mongolian from the beginning, but that the climate they lived in for a long time, and historical Finnish immigration and assimilation of Germanic tribes (Teutons)—which he considered modern "pure Finns" indistinguishable from—had made the Finnish population one of the whitest people in Europe. If the Finns had Mongol ancestry, it was distant and diluted. John Svan and the others were made naturalized US citizens, and from that day on, the law forbade treating Finnish immigrants and Americans of Finnish descent as not white.

https://en.wikipedia.org/wiki/Definitions_of_whiteness_in_the_United_States#Finnish_Americans

Italians had no protection under the law in the US for a period of time. Italians were considered to be white and we're not given any protection.

The 1891 lynching of eleven Italian men in New Orleans following the murder of police chief David Hennessy highlighted this precarious position. Though legally white, Italians were not fully accepted into the social privileges associated with whiteness. Public reactions to the lynching often portrayed Italians as inherently criminal and racially suspect.

https://en.wikipedia.org/wiki/Definitions_of_whiteness_in_the_United_States#Italian_Americans

This is why racism is a social construct created by the ruling class. The definition of whiteness can and will change at the behest of the ruling class to justify oppressing anyone who doesn't fit the the parameters of being white. Even though historically Irish, Eastern Europeans, Finnish, and Italians have skin color that is white and are not considered white.