In response to evidence of profound injustice in the world and our powerlessness to right things, some people relieve the stress of that realization by convincing themselves that the world isn't so unjust after all.
This isn't just "blame the victim", it potentially explains valorizing the rich in America. The Horatio Alger myth part of the American Dream contributes to it, as well. We believe that rich people have earned and deserve their success, and are reluctant to 'penalize' them through taxation.
You needn’t be explicitly racist or sexist to hold such views, nor committed to a highly individualistic political position (such as libertarianism); the researchers controlled for those. You need only cling to a conviction that the world is basically fair. That might be a pretty naive position, of course – but it’s hard to argue that it’s a hateful one. Similar associations have been found between belief in a just world and a preference for authoritarian political leaders. To shield ourselves psychologically from the terrifying thought that the world is full of innocent people suffering, we endorse politicians and policies more likely to make that suffering worse.
Oliver Burkeman, Believing that life is fair might make you a terrible person