Protecting Christianity, Trump essentially argues, is a job for a bully.

Hi, I'd like to ask the meaning of "job for a bully" in the paragraph below.

I think Trump is taking advantage of evangelists and that is the point of this paragraph, but don't get why "protecting Christianity is a job for a bully" I think bully here means American secularism, and .. "protecting Christianity is a job against bully' makes more sense. But I am not sure anyway.

"Trump consistently depicts evangelicals as they depict themselves: a mistreated minority, in need of a defender who plays by worldly rules. Christianity is “under siege,” Trump told a Liberty University audience. “Relish the opportunity to be an outsider,” he added at a later date: “Embrace the label.” Protecting Christianity, Trump essentially argues, is a job for a bully."

Thank you in advance.