In his new book “What to Expect When No One’s Expecting: America’s Coming Demographic Disaster,” Weekly Standard senior editor Jonathan V. Last strikes a dour note about America’s demographic trend.

“We’re not having enough babies. Doom to follow,” Last told The Daily Caller in an interview.

“Once a country’s fertility rate has been sub-replacement for a couple generations, its age profile inverts so that there are more old people than children,” he continued, expounding on the doom he predicts will follow.

“The economy stagnates because there are too few innovators and entrepreneurs and there isn’t enough investment capital. The entitlement state teeters on collapse because there aren’t enough workers to support all of the retirees. And the country loses the capacity to field an effective army because (1) the pool of military-aged men and women is too small and (2) defense gets cut in order to prop up Social Security and Medicare.”

According to Last, that’s actually “the best-case scenario.”

“The worst-case is that you wind up in something like Mad Max, only with the Thunderdome being run by Grandpa Simpson,” he said.

Which is why Last concedes that Octomom could actually be considered “the greatest hero of all” for doing her part to increase America’s fertility rate.

But isn’t America’s demographic problem far less serious than that which is faced by countries in Europe and Asia?

“Sure, I suppose. In the same way that a woman who just got knocked up is less pregnant than a woman in her second trimester,” Last said.

“Look, the Europeans are ahead of us and the Asians are ahead of them, but we’re all on the same curve and that curve runs straight to Doomsville.”

See TheDC’s full interview with Last about his book and whether we can reverse our demographic course below.

Why did you decide to write the book?

I became slightly sort of totally obsessed with demographics several years ago after reading Phil Longman’s masterpiece, “The Empty Cradle.” Demographics is one of those subjects, like numerology or celebrity breast implants, where once you start looking at it, you see it everywhere.

Also, you’ve probably heard how the publishing industry is having this Golden Age right now because of the Internet. I figured it was a good time to hop on that gravy train. The Reverend’s gotta eat.

What is America’s coming demographic disaster?

We’re not having enough babies. Doom to follow.

Look, I’ll be straight with you: Having kids blows. You spend 25 years working like a dog to arrange your life in a very particular manner: You go to the gym, you read lots of interesting books, you take cool vacations, you watch football on fall afternoons and catnap during the commercial breaks. You hang out with friends in the evenings to have elevated discussions about Kierkegaard and/or drink yourselves stupid. Life is so good you can taste it in your spit.

And then you have a kid.

That life you built for yourself? It does not diminish by 20 or even 80 percent. It is utterly and totally obliterated. Napping on the sofa during football doesn’t become an occasional treat. It becomes nothing more than a rumor of some lost age.

If you have a baby you will never doze on the sofa while watching football again. This is a point I cannot emphasize enough.

So, like I said, we’re not having enough babies because people enjoy having interesting, fun, lives.

This may not sound like such a bad thing, except that when a society doesn’t have enough babies, all sorts of Very Bad Things happen.

Basically, our choice is to ruin our own lives by having kids, or ruin everyone’s life by not having them.

Or, as P.J. O’Rourke says in his brilliant blurb for “What to Expect When No One’s Expecting,” “The only thing worse than having children is not having them.”

What will the consequences of it be for the nation?

Once a country’s fertility rate has been sub-replacement for a couple generations, its age profile inverts so that there are more old people than children. The economy stagnates because there are too few innovators and entrepreneurs and there isn’t enough investment capital. The entitlement state teeters on collapse because there aren’t enough workers to support all of the retirees. And the country loses the capacity to field an effective army because (1) the pool of military-aged men and women is too small and (2) defense gets cut in order to prop up Social Security and Medicare.

That’s the best-case scenario, by the way. The worst-case is that you wind up in something like Mad Max, only with the Thunderdome being run by Grandpa Simpson.

You think I’m kidding about generational warfare, but a couple weeks ago Japan’s Finance Minister said publicly that old people ought to “hurry up and die.”

(Only slower. And with more intensity.)

Can our demographic disaster be averted? If so, how?

Absolutely. I’ve got a 59-point plan in my book and if the policy establishment would just follow my suggestions, we’ll be five-by-five.

Not really. We’re screwed.

One of the lessons of looking at this demographic stuff is that most people are hostage to their own experiences. Well-meaning liberals on the Upper West Side mostly think that we can solve our demographic problems just implementing the policies they like—such as government-subsidized daycare and mass immigration. And nice conservatives often think that we can fix everything by reforming the tax code and returning to traditional values.

But there’s a lot of research on this stuff and the data suggests that neither approach is particularly effective.

What I suggest in the book is that if we’re going to make any headway, we need to start by looking at the data. Then we make Nate Silver “Czar of Baby Making.”

In a way, do you consider Octomom a hero?

Some would say she’s the greatest hero of all. And when she finally gets her Cinemax-style, soft-core three way with Kate Gosselin and Michelle Duggar, American men will stand up and salute as one.

Isn’t America’s demographic problem far less problematic than the demographic problems faced by European and Asian countries? Our fertility rate is relatively high comparatively and we do a better job of assimilating immigrants than Europe, no?

Sure, I suppose. In the same way that a woman who just got knocked up is less pregnant than a woman in her second trimester.

Look, the Europeans are ahead of us and the Asians are ahead of them, but we’re all on the same curve and that curve runs straight to Doomsville.

Here’s the thing about America’s relatively high fertility rate—it’s due entirely to Hispanic immigration. Strip out our Hispanic immigrants and we look exactly like Europe.

And Hispanic immigration presents—from a demographic perspective, put other considerations to the side for now—two big problems. First, it’s not going to last. All the countries of Central and South America will have fertility rates below the replacement rate in 20 years. Which means they’re going to stop sending us immigrants. Second, the fertility rate of Hispanic-Americans is falling even faster than it is for everyone else in the U.S.

They’re not going to do the heavy demographic lifting for much longer.

You have a chapter in the book called “How to make babies.” How graphic does the chapter get?

It’s a pretty hot read, actually. I know I’m not supposed to give too much away, but there’s a good section about how, when a man loves a woman very much, and he’s able to concentrate and picture Mickey Kaus and Matt Labash standing in a clear Wyoming river, holding their fly rods and wearing nothing but hip waders—then sometimes they can express the miracle of their love together.

And then share it on RedTube.

How does our demographic problem relate to our looming entitlement problems?

It’s pretty simple, actually. We have lots of old people lining up to collect Social Security and Medicare. We don’t have a lot of young people working and forking over the tax money to pay for all those goodies.

What’s worse is that once you hit 65, the government doesn’t care whether or not you had kids. They give you the bennies either way.

Think about who’s paying for those bennies. You know what economists call babies? “Future taxpayers.”

Now, it costs a lot of money to make a future taxpayer—as I calculate in “What to Expect,” on average a kid costs over $1.1 million, once you count college tuition and lost parental wages.

Here’s the rub: The people who spend millions of dollars making and raising the future taxpayers (who then fund Social Security and Medicare) get the same benefits as the people who save their money by not having kids.

Economists call this sort of thing “moral hazard.”

What is the most interesting – or perhaps alarming – anecdote or statistic you discovered researching this book?

You want to know how real all of the “moral hazard” stuff is? Over the last few years two studies have suggested that Social Security and Medicare depress the American fertility rate by 0.5 kids. In other words, the average American woman has half a kid less than she would otherwise, just because of those two programs.

In the end, are you bullish on America to overcome the challenges you see? Or is America in inevitable decline?

Nothing is inevitable. Trends change. We could collectively choose to start having more kids tomorrow and all of these problems would disappear.

All of that said, take a look around modern America. Does this look like a country where we value the continued health of Western civilization? Or does it look like a place where people would rather fall asleep watching football?

Look—no judgments here. I like football naps, too. I love the child-free yuppie paradise. It’s great.

Which is why I’ll take “inevitable decline,” plus the points.

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