immune to shame

Jennifer WeinerのFly Away Homeを読んでいますが、そうだよなと思う箇所がありました。
He’d have simply bounced the baby in his arms and sung “New York, New York” to her, loudly and off-key, impervious to the stares and rolled eyes and loudly heaved sighs of his fellow travelers. You couldn’t embarrass Richard. He was immune to shame the same way some people never caught colds. It was why she thought he actually could be president someday—unlike the vast majority of people walking the earth, he could withstand a campaign, and all the things his opponents would say about him; he believed in himself, and no amount of criticism could convince him that he shouldn’t.
Richardはインターンとの不倫を暴露された代議員です。連想したのはどこかの国の大統領やどこかの国の首相です。どこかの首相は不倫はしていないと思いますが、怪しいことをしているにも関わらず、知らん顔をしていることは同じです。 "immune to shame" は大物になる素質の一つなのですね。