"I've been trying to understand the "Gates of Hell" argument raised in conservative media. It seems to run along the lines of, "If Democrats can indict a Republican that hasn't done anything wrong, then they'll hate it when Republicans indict Democrats that haven't done anything wrong."

I too have been trying to figure out why this argument is so persuasive in the nutter media. I mean it is clear that they have little understanding of the Grand Jury and indictment process. If a conservative DA tries to go after an innocent Democratic politician, it is not a simple process to impanel a Grand Jury and then try to get them to indict with no evidence. Furthermore, the DA in opening themselves up to sanctions and all sorts of other punishment. Doing this is a bigger deal than they realize.

So I have been trying to understand why they think it will happen. Then I remembered that you need to think like a Trump supporter. A Trump supporter doesn't look at the evidence and then arrive at a conclusion. He starts with a conclusion and then looks for evidence to support it (ignoring things that don't).

So if you start with the conclusion that this is only being done as a political ploy, then it is easy to arrive at the idea that DAs everywhere will start doing it.

They just don't want to acknowledge that it isn't just a political ploy. There are actual crimes there.