Distractive. (RICHARD SHIRO/AP)

One is “a project that is just lying there waiting for someone to grab it up and run with it.” The other is the same but smells worse.

Birtherism is both of these things.

Is there anything you can do to extinguish this movement? Or is it some sort of horrifying political cockroach that scuttles across your wainscoting just after the exterminator has departed?

I fear that it’s the latter.

In May, after the president, with due fanfare, had wheeled out his long-form birth certificate so that Doubting Birther Thomases could touch the holes in its sides and say, “Hurm,” to themselves, 3 percent of Americans still said they believed Barack Obama was not born in this country.

And a further 20 percent said they had no opinion.

Sounds like a cockroach, all right.

Now Rick Perry’s courting the birthers and the I-don’t-knowers (Know-Nothings was taken) with a series of cryptic statements about how he doesn’t know if the president’s birth certificate is real, but hey, it’s a distraction anyway.

Look, if you are a birther who is reading this because someone has excerpted the phrase “horrifying political cockroach” and placed it on a blog you frequent, I do not think you are a bad person or that you are intellectually deficient. People seldom are. That would make the world too simple.

I am just curious as to why you think this is a remotely important issue. Or do you not, in which case Perry’s stratagem is pointless and ham-fisted? This would not be a first for him.

Is the logic that, “If it turned out to be true, it would be ground-shaking and unsettle all we thought we knew?”

That is true of almost anything! Aliens. The Yeti. “What if our government is secretly run by a series of machines who are feeding off our bodies, exactly like the ‘Matrix’ trilogy?” If true, that would indeed be groundbreaking. But I don’t involve that consideration in my voting decisions. There are too many, well, real-er things to think about.

“Have you seen the birth certificate in person?”

Is this the standard now? I haven’t seen Rick Perry in person either, but I still believe he exists.

I believe in many things I have not seen. I believe in gravity. I believe that at one point God wandered down to Earth and handed out free fish. I believe in neutrinos and in George Lucas’s good intentions.

At a certain point, you have to settle on some basic assumptions about the reality of the world around you. Otherwise you’re stuck at a desk for several years murmuring, “Cogito ergo, cogito ergo, uh, uh,” and your neighbors start passing remarks.

Why are we still talking about this?

Look around you. “All I see is my cubicle.” Go outdoors.

There is a recession. There are people in tents. There is a general stirring in the street. People on both sides of the aisle mistrust government intensely — 89 percent of Americans don’t trust their government to do the right thing.

But there are constructive things to do about all this. Read an economics textbook. Read another conflicting economics textbook. Kidnap economists and force them to fight to the death. Sign a petition. Close your Bank of America account. Familiarize yourself with foreign policy, and write irate letters to the editor about it. All of the above. None of the above.

Anything but this. Tea Party. Occupy. Pick your poison. Just stop talking about the birth certificate.

The argument is outworn, smells horribly, and it’s a waste of everyone’s time.

Jeb Bush repudiated it. So did Bob McDonnell. Jon Huntsman recently tweeted that the birther question was a wasteful distraction and we ought to focus on the economy. But if I had a dime for every time someone called the birther issue a wasteful distraction and it didn’t go away, I’d be in the 1 percent by now.

Why, why, why is this issue alive? It’s a make-work issue for curmudgeons with nothing else to kibitz about. It might make sense if there were nothing else going on. But there is everything in the world to complain about! Rick Perry is completely right: It’s a distraction!

This whole story reminds me of a tale that has recently gripped D.C. and its suburbs — the dog poop case. A woman was on trial for allegedly failing to pick up the droppings of the bichon frise she walks. Experts were called. Samples were analyzed. Eventually she was cleared.

Meanwhile, dozens of people had wasted days staring at dog feces.

That’s this issue, in a nutshell.