Please answer a question about the following article about The Sun (United Kingdom):

Hopkins' column also drew criticism on Twitter, including from Russell Brand, to whom Hopkins responded by accusing Brand's "champagne socialist humanity" of neglecting taxpayers. Simon Usborne, writing in The Independent, compared her use of the word "cockroach" to previous uses by the Nazis and just before the Rwandan Genocide by its perpetrators. He suspected that if any other contributor had written the piece it would not have been published and questioned her continued employment by the newspaper. Zoe Williams commented in The Guardian: "It is no joke when people start talking like this. We are not 'giving her what she wants' when we make manifest our disgust. It is not a free speech issue. I’m not saying gag her: I’m saying fight her".

With whom did Usborne draw parallels to Hopkins as a result of Hopkins' comments?
previous uses by the Nazis and just before the Rwandan Genocide by its perpetrators