Suppose, for the sake of argument, that you are the Chinese Communist Party.

It's the 1950s, and you're a young, headstrong, take-charge, kind of political movement. You've driven the Nationalists off the mainland, established the first government of a unified China in perhaps a century, and now, to complete the hat-trick, you're going to catch China up to the developed West and restore its rightful place among the great nations of the world. But how?

Now the nay-sayers would say, and you have to admit they do have a point, that one of the major preconditions for rapid development is going to be solving China's food crisis. Conservative estimates are that China has been overpopulated since the late Ming dynasty. And her population has only gone through the roof since then. Too many people, not enough land, agricultural technology that was modern six centuries ago, you're going to have problems just feeding your industrial workers, let alone building industry for them to work in.

But you, if you're anything like the CCP of the 1950s, are anything but a nay-sayer. And what those nattering nabobs of negativism see as China's greatest weakness --- its huge and impoverished agrarian populace --- you see as China's greatest strength.

Quiz time. Why might a huge and poor agrarian populace be a strength?

As Chairman Mao realized, the true source of revolutionary power is the rural peasantry. It's just about the First Rule of proper revolutionary doctrine that any societal problem can be solved by mobilizing the peasantry.

The People's Liberation Army tried it, and they fought off both the Japanese and the Nationalists. So did the Chinese Communist Party, and they rebuilt China's national political identity. And when you think about the economic challenges of modernization, a whole lot of them seem like prime candidates for solution-through-mobilization.

Inefficient microscopic byzantine plots of land? Massive communes working millions of acres in precisely regimented Production Teams will create massive economies of scale. Want to irrigate large river valleys and built a few thousand factories? Human labor can realize public works projects of record-breaking scale.

Quiz time: can you think of any other problems you might be able to solve by mobilizing the peasantry?

Even problems not typically admitting of engineering solutions can be dealt with through revolutionary means. Heavy industry needs raw iron to jumpstart? The molten-down pots and pans of the peasantry will meet the demand. Corrupt local officials blocking reform efforts? Start a campaign against corruption. Or how about public health problems? Start a campaign. Thus the Four Pests campaign --- an effort to rid China of the malign influence of those four nasties: rats, mosquitoes, lice, and sparrows.

Sparrows, you ask? Mosquitoes, sure, bloodsucking disease-carriers, drain the swamps, yadda yadda yadda. Rats, no problem, they eat our food, live in filth, keep nasty company like the bubonic plague, and are darn ugly, besides. Lice, okay, there're reasons why every schoolkid in America gets a head lice screening by the school nurse once or twice a year. But sparrows?

Quiz time. Why sparrows?

Sparrows eat grain. Should a sparrow come across a kernel of grain on the ground, said sparrow will eat said kernel. When you have large numbers of sparrows hanging round, this has certain implications for your planting methods. Should you, for example, attempt to scatter seeds across a furrow, you would be lucky if the sparrows looking on would wait for you to take three steps away before they swooped in to eat each and very seed.

Should you take the time to carefully bury the kernel and cover it with a layer of earth, the sparrows will have a harder time getting at it; it might even stand a fighting chance of living long enough to put down roots and become a harvestable, growing, living, thing. The sparrows attack the growing cycle at its most vulnerable point, slashing yields, inhibiting the use of modern agricultural technology, and drastically forcing up the amount of human labor required during planting season. Damn sparrows.

But how to get rid of them? Shoot them? That'll take forever, waste tons of ammunition, and leave the fields covered in spent bullets. Poison? Probably not the best idea, taking some of your already-scarce grain supply and deliberately ruining it, plus it takes poison that's safe to use on food-grain fields. Traps? The mind reels at the number of traps required. And all of these methods share the common problem that they will kill, at most, only a moderate fraction of the sparrow population.

Quiz time. How DO you kill large numbers of sparrows quickly?

Stuck? You're forgetting the First Rule. Mobilize the rural peasantry.

It's actually an amazingly simple idea. You get everyone in the village together and go out to the fields where the sparrows are. Then you have everyone run around banging on pots and pans and screaming loudly. The sparrows get frightened and take to the air. Now you just have to keep on making noise for a while.

After about fifteen minutes or so, the sparrows, still too terrified to land but also too dumb to fly somewhere else (especially because a village-ful of people can conver quite a lot of ground) are going to get pretty tired. In fact, they're going to get so tired that they'll drop out of the sky from exhaustion. And when Comrade Sparrow falls to earth, all you need to do is run over and wring its neck, and there you go, no more Comrade Sparrow.

Not only is it simple, it's also stunningly effective; over the course of a few hours, you can kill more sparrows that you know what to do with. There are photographs taken of teams of smiling peasants standing in front of twenty-foot high mountains of dead sparrows. Kill fifty or a hundred, and you get a Mao button, a proud emblem of your revolutionary anti-sparrow zeal.

Incredible as it may sound, this tactic works. Overnight, the sparrow population in Northern China falls to a small fraction of its former size. The CCP hands out a ridiculous number of Mao buttons. As hoped, agricultural yields skyrocket to record levels. The harvests are wonderful.

Quiz time. What is wrong with this picture?

Nature, of course, abhors a vacuum. And nature is pretty good about setting up ecosystems in which every piece plays a role. Consider, for example, the food chain. Consider, for example, what happens when you delete a link in the food chain.

Now, it's not a problem higher up, in the slot labelled "things that eat sparrows." It's not as though humans are particularly dependent on sparrow predators. Nor do we eat usually sparrows. Sparrows certainly aren't generally a part of this complete breakfast. The recommended daily allowance of sparrow meat is zero. No, we're talking about a problem in the other direction, with the next slot down in the food chain, the one labelled "things that sparrows eat."

Quiz time. What, besides grain, do sparrows eat?

Locusts. Sparrows eat locusts. With no sparrows around, suddenly the major check on the locust population has been removed. The harvests are amazing the first year, and the next year witnesses the worst locust infestation of China in living memory. The locusts are so thick they blot out the sky; they settle across the fields like a living blanket from one end of Northern China to the other. Yields plummet.

Estimates are that up to thirty million people died in the resulting famine.