Does the size of Donald Trump’s penis matter?

I’m not being cheeky. I’m not being shocking. I’m noting something that we cannot lose track of, should not shrug our shoulders about and must not gloss over: Trump has succeeded at nothing as fully as he has at infusing the presidential race with a vulgarity that’s absolutely breathtaking.

He has done so well at dragging his rivals so far down into the sewer with him that portions of what we watched on Thursday night were a fetid farce. We actually witnessed an interchange — in the first 10 minutes, no less — about how well endowed (or not) he is.

It’s worth stopping for a second, letting that sink in and wondering what it says about our country and political process right now.

Here’s how it happened: One of the moderators upbraided Marco Rubio (rightly) for abandoning incessant pledges of a positive campaign, answering Trump’s schoolyard taunts with adolescent jokes and jabs of his own, and even going so far as to claim that Trump had wet his pants under the pressure at the prior debate.