Oh for gods sake. user
Can white people experience racism? Yes. I think the abduction and torture of the white special needs guy in America last week shows that. Screaming fuck the white boy, black power! whilst torturing somebody does kind of show that...
or the (black) couple kicking a white woman lying on the ground whilst screaming something along the lines of not in our hood, white bitch.
So, if you have been the victim of racially motivated things like that? Yes. You have experienced racism. But most white people in a primarily white society have not made these experiences (luckily! I don't want anybody to be assaulted or discriminated against).
But being a minority isn't the same as being a majority. Whether that's because of a disability, sexuality, race, religion...
this does not mean that the opinions of people from the majority don't matter, or that somebody that's in one majority group can't be in an other minority group.
Or that people that have never been in the minority can't empathise.
But can the majority dictate what the minority is allowed to feel offended by? No!
I personally do believe that my experiences with homophobia and sexism do grant me a higher degree of empathy with people from other minority groups or anybody that has experienced an ism.
And who knows, maybe the OP has a lot of experiences with being otherised, stigmatised or people being prejudiced against her. And maybe that's why she made this post. Knowing that whilst she has made many experiences she has not made experiences like that because of her race.
I think that's a credit to her. I'd worry more if she didn't think about these things!
A white person growing up in Korea may make similar experiences of being 'otherised' and feeling different than a Korean person in a primarily white country.
But we are talking about the UK. A country where white people are not a minority.
So, yes. Most white person will not have personally experienced racism the way a black person or an Asian person or a Latino in the U.K. would.