Oppression enforces itself through the codification of its ideals
Anyone can enforce whiteness and benefit from its protections.
How oppression affects the individual.
Everyone is harmed by whiteness; the ways it interacts with you through societal oppression varies.
I'm a cis-hetero-white-male.
Our society has been dictated by white supremacy and patriarchy. I have been conditioned deeply to enforce whiteness and therefore can do the most harm.
Understanding the ways you can enforce whiteness are important in limiting that harm. It is also important to actually recognize the harm you do or have done regardless of your intersectionality.