One of the best long-term predictors of economic strength is demographics. Countries that have gradually increasing populations have huge advantages over countries that have declining populations. The reason is the ratio between working-age people (roughly 15-64) and non-working-age people. Working-age people are productive. They invent things, build things, start businesses, earn money and invest that money. Countries with growing populations have significantly better ratios of working-age to non-working-age people than countries with declining or stagnant populations.
There is only one affluent country that can expect the size of its working age population to increase over the next several decades: the United States. Generally speaking, as countries grow more affluent, their people have fewer children. The replacement rate—the birthrate necessary to maintain a stable population—is about 2.1. Japan, the world’s third largest economy, has a birthrate of about 1.4. That is part of the reason that China has surged past Japan to become the world’s second largest economy. However, about 20 years ago, China dropped below the replacement rate (largely due to the one child policy) and its birthrate is now down to about 1.5. This has not yet slowed the Chinese economy because people below the age of 20 are not very productive. However, the problem will catch up with China over the course of the next 50 years and make it much more difficult for China to catch to the United States in GDP than many people assume. Western Europe has a stagnant population, due to low birthrates, and Russia has a decent birthrate but a horrible public health situation that is decimating its working-age population (partially due to the country’s love affair with vodka).
Yet, the United States can expect its population to grow by a healthy 20% between 2010 and 2030. There are two reasons for this: a relatively high birthrate and a constant influx of immigrants. The birthrate is difficult to explain, but it could have something to do with the US’s relatively low population density.
Immigrants tend to be quite young, and they tend to be capable of being very productive. This means that they are very good for the economy. In The Post-American World, Fareed Zakaria discussed the importance of immigrants in a slightly different way. He pointed to an historical trend of superpowers becoming complacent. In order to remain on top, the people of a country must maintain the fire that got them there. The United States has somehow kept that fire well after obtaining superpower status. Zakaria attributed this to the constant influx of immigrants. These are people who have not been part of the past victories of the country and want to create their own success stories. The immigrants create internal competition, which prevents the native-born citizens from becoming complacent. Thus, based on either the cold mathematics of demographics or the more interesting (yet questionable) Zakarian fire-in-the-belly theory, immigration is good for the United State’s economy.
To a large extent, the US is lucky to be in a strong demographic situation. As Otto Von Bismark put it, “A special Providence protects fools, drunkards, small children and the United States of America.” Yet, Americans must take advantage of this luck. My former priest once told the following story:
“A religious man became stranded in a flood. He prayed to God to save him. After a while, a row boat came along. The men in the boat told the religious man to get in. He refused, saying ‘God will save me.’ The water continued to rise, and later, a motor boat came by. The man against said that he had faith that God would save him and refused help. Finally, the water rose nearly to the top of the roof. A helicopter came and offered the man help. He sat there on the roof, declined help, and he continued to pray. The man drowned. He went to heaven and confronted God. ‘I was a devout man, and I prayed for help. Why didn’t you save me?’ God replied, ‘I sent two boats and a helicopter, what else did you want?’”
America is lucky to be in a favorable demographic position. Only fools would fail to take advantage of it. The best thing it could do would be to help the immigrants become as productive as possible by providing a path to citizenship which requires education, learning English, public service and staying away from crime. That is what the DREAM Act does, and that is why it should pass.
 Seriously, how many people live in Wyoming? 16? 17?