I think we’ve missed one possible explanation for Rudy Giuliani’s behavior: Maybe he’s concealing the fact that he suffered a blow to the head severe enough to cause lasting damage to his prefrontal cortex. For those who haven’t done a Web search as I have, so I can now pretend to know what I’m talking about, the prefrontal cortex is the high-function part of the brain that controls, among many things, the ability to inhibit impulses, allowing us to regulate what we say and do. Actually, chances are that it’s not that at all, that Giuliani is continuing his very calculated effort to stay relevant by appealing to the ugliest emotions of the Republican Party’s base.

You decide what caused him to say what he did at a New York dinner: “I do not believe, and I know this is a horrible thing to say, but I do not believe that the president loves America.” So he knows it was a horrible thing to say but he said it anyway. So that eliminates the insanity defense. And he’s not backing down. And why should he?

The extremists actually aren’t all that extreme in today’s GOP. The party has encouraged the birther notion, which is to say that Barack Obama wasn’t even born in the United States and is therefore ineligible to be president. The accusation persists despite having been disproven every which way but Sunday. The demagogues continue to peddle that idea, along with the poisonous claim that the president is not the Christian he claims to be, but is actually a closet Islamist.

All of this revolves around the outrage by many conservatives that Obama got elected chief executive in the first place — oh, and in the second place, four years later. Still, they simply cannot accept the idea that the country’s leader — whose middle name is “Hussein” and doesn’t look like most of them (and you know what that means) — is really “one of us.”

So let’s dismiss this as simply Rudy being Rudy, but what’s galling about it is that the administration wimpily found it necessary to respond. No, I’m not talking about press secretary Josh Earnest telling reporters, “I feel sorry for Rudy Giuliani today.” That would be appropriately dismissive.

It was President Obama who made it a point to tell the Democratic National Committee that the party agenda is “about making this nation we love more perfect.” The White House will claim that POTUS often talks about how he “loves” America. But clearly, he or his handlers needed to make sure he said it while Giuliani’s invective was bouncing around the political darkness.

Certainly we have to wonder why the Rudy Giuliani comments get any circulation whatsoever. We can attribute that to the simple-minded, incendiary sound bite nature of policy debate this days. Frankly, that’s on us in journalism. What we have spawned is a society that is almost incapable of comprehending nuance and complexity.

So we come up with terms like “American exceptionalism” and the mindless argument that if someone doesn’t believe that the United States is inherently superior in every way, he or she is unpatriotic. It’s a descendant of “America: Love it or Leave It.” Critics of the U.S. of A. can just ship out. Never mind that we trail the developed world in a number of essential metrics that measure education and medical care, and never mind that our missteps have made bullying the planet’s other countries no longer possible.

So when President Obama tries to be evenhanded, he is fair game for the demagogues who exploit the desire for a return to the America that was, although that was largely a fiction, too. And that’s what Rudy Giuliani is: a demagogue whose hateful rants are amplified by media who thrive on hateful rants. Shame on him. Shame on us for paying attention. We should have our heads examined.

Bob Franken is a longtime broadcast journalist, including 20 years at CNN.