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News How big should the US population be?

Optimal size of the US

Poll closed Oct 10, 2011.
  1. 100 million

  2. 200 million

  3. 300 million

  4. 500 million

  5. 1.2 billion like China

  6. I can't say I care

  1. Oct 3, 2011 #1
    I was listening to the news today, and the issue touched briefly on population size. And, for fun, I was just wondering how big people in the US think their population size should be. This is meant to be informal, just imagine how you would like your country to look a century from now.
  2. jcsd
  3. Oct 4, 2011 #2
    A decrease in population over the next century would require a some sort of crisis or extraordinary circumstances. An explosion of population to more than a billion might require a flood of refugees - and perhaps a crisis or extraordinary circumstances? Accordingly, the projected 500 million sounds the most realistic.
  4. Oct 4, 2011 #3
    Yah, I think I outdid it with postulating a 1.2 billion target.

    It's a bit of a local Dutch thought of me. I am somewhat convinced that we need to decrease our population 1/3 short term, and 1/2 long time, in order to grow a sustainable country.

    So I was also wondering about what people in the US would think is best for their country. But it's a completely different setting since my country has 400 persons per square kilometer, and the US about 34.
  5. Oct 4, 2011 #4
    Are the age distributions of your population such that this decrease may occur naturally?
  6. Oct 4, 2011 #5
    The Netherlands is pretty typical for Northern Europe, except for its high density. The demographics of most of Northern Europe are such that most populations have a fertility rate of less than the 2.1 children per woman needed to sustain the same population size. Because of WWII, or rather the babies born after that, most populations in Northern Europe now have a heavy top of old people. Most populations in Northern Europe, and the Netherlands, are still rising because of immigration, where Germany is the sole exception to that. (I think they figured out the anticipated problem: food production will halt abruptly if oil supply stagnates sharply.)

    So yeah, without immigration the population size would drop, but very slowly. Not fast enough for what I'ld like, anyway.

    The US has the opposite 'problem' of Northern Europe, with a lively and young population, btw.

    (Though I did some calculations. Dutch fertility is 1.77. If I halve that and take a power of 10 of it, [STRIKE]a decade,[/STRIKE] oops, ten generations, it falls pretty steeply.)
    Last edited by a moderator: Oct 4, 2011
  7. Oct 4, 2011 #6
    Shouldn't your population density of 400 persons per square kilometer be a deterrent to immigration?
  8. Oct 4, 2011 #7


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    A country wide average of 400 is really high (that's equivalent to about 1000 per square mile). The US has an average of 32 per square kilometer, while Mongolia has an average of 1.7 per square kilometer.

    But, 400 isn't incredibly high for a city in the US. There's 275 cities in the US with a poluation over 100,000 and only 10 of them have a density less than 1000 per square mile. The least dense would be Anchorage with only 171 per square mile. In fact, the major metropolitan areas have densities over 10,000 per square mile.

    Even in the US, immigrants would be more likely to move to the city where there's jobs, not to the areas of the US where the density is the lowest.

    In other words, there's trade-offs either way. Along with that high density urban population comes the chance for employment and the chance for employment is probably a lot better in the Netherlands than in Mongolia. I'd expect current Netherlands residents to be a lot more resistant to admitting new immigrants, though.
  9. Oct 4, 2011 #8
    No, it's not so high if you look at how the majority of the country looks like. It's mostly one big agglomeration of villages and cities, with some major cities.

    I once talked to an American who said that driving through the Netherlands is somewhat akin to driving through lots of suburbs; once you're out of one, one mile later you drive into the next. It doesn't even feel crowdy, there are lots of lovely small villages with old churches and fields, rivers, dikes, dunes, and forests around.

    You never get to to get to a place where you can't hear another person or car, though.

    It's not sufficient to stop immigration. People are pretty wealthy, we're about par to US standards, though stuff tends to be smaller (housing, cars, etc.). Also, we've got an unemployment rate of 4-5% and virtually no lower, or upper, class.

    It is also not crowded enough that people really experience it as a reason to stop immigration. My reason is a bit goofy to the most of the people in the Netherlands, I imagine.
    Last edited by a moderator: Oct 4, 2011
  10. Oct 5, 2011 #9
    Doesn't sound like there's enough land to sustain the population 100% in both feast and famine (well, lean production times).

    I voted for 300 mil. Can't exactly kick out the ones who're already U.S. citizens, but do we "need" more? No, and no one has a "right" to immigrate to another country. It's the country's prerogative.

    Well, that's relative. Someone living in Tokyo would undoubtedly be comfortable in New York City. They'd probably be uncomfortable throughout most of the U.S.

    However, crowding isn't the problem. Food might be had from other countries in times of peace, but what about in times of war? Our planet has not been without war in at least 10,000 years, and that includes the last 10 years. Surplus food production is a strategic resource, and allowing population levels to eclipse that is foolish.

    There are several other key strategic resources.

    My reason is a bit goofy to the most of the people in the Netherlands, I imagine.[/QUOTE]
  11. Oct 5, 2011 #10
    Hmm. I don't care too much about war. It's just that if I informally add up the global energy consumption numbers, my best guess is that -in about forty years- the lack of oil will be disruptive, and we'll probably witness the reintroduction of horses on farmers' fields. If that happens globally, the mess we'll find ourselves in won't be pretty. (Though war may certainly be a part of that.)
  12. Oct 5, 2011 #11
    I put 500 million. Not that I think it's optimal, but that projections indicate that that's what it will be in about 100 years.

    I don't think it makes much sense to talk about optimal population. No point in entertaining attractive fantasies that probably aren't going to happen. Better to consider what we will do during the next 100 years with the expectation that the population will reach 500 million -- and maybe not stabalize at that number.

    In fact, this is a rather conservative estimate. It's projected that the US population will be at least 450 million by about 2060. Some people have it stabalizing at that number. But I don't think that's going to be the case ... unless the mortality rate significantly increases and life expectancy becomes quite a bit less than it is now. Which could happen of course.

    In any case, the outlook for the US seems quite grim.
  13. Oct 5, 2011 #12
    Billions is fine. They should just all move out of Midtown Manhattan!
  14. Oct 5, 2011 #13

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    Even with its draconian one-child rule and its less draconian predecessors, China's population has grown for the last forty years and will continue growing for another twenty. There are no humane short term solutions to an overpopulation problem, unless your meaning of "short term" is a century or so. There are some downsides to Western Europe's and China's less-than-replacement birth rate. One is who will pay the taxes that will sustain Western Europe's burgeoning aging population?

    With regard to the US, our birth rate would also be below replacement were it not for recent immigrants, legal and illegal, who tend to have larger families.
  15. Oct 5, 2011 #14
    I voted for 500 million. There's me, my wife, my son upon whom I cannot rely in my old age, and my daughter who is a bump on a log. It will be up to the other 499,999,996 to support us.
  16. Oct 5, 2011 #15
    Even an aging population can be supported without problems. It's just that most moms and dads are tied up with their family around an XBox that it is even a problem.

    I just don't see why we wouldn't let it dwindle down in Europe anyway, given the long term perspectives. Are we helping other countries by absorbing their surplus so that they can even procreate more?

    On the long run, a growing population means that you end up sharing the poverty of my country. A bit less now, to have more in the future, just looks prudent to me.
  17. Oct 5, 2011 #16

    D H

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    Baloney. Mom and Dad cannot pay the bills that accrue when Grandma and Grandpa becomes so physically or mentally disabled that home care is no longer an option. Neither can the various social security / public pension systems in the western world. The prospect of a burgeoning aging population coupled with a dwindling tax-paying base is a widely recognized problem throughout the western world.

    That is a false dilemma. This is a problem when the population grows out of control, which is one of the many problems that confront third world nations. It is not a problem in the developed countries. Moderate population growth is not a problem now, and won't become a problem for a long time. In western Europe, lack of population growth is a problem today. Your public pension systems are even more stressed than is our Social Security system.
  18. Oct 5, 2011 #17
    Great, we have a debate! No, I don't see any reason why we can't take care of our aging population. If we have to, we will, it's as simple as that. The problem is that we want to take care of them, but at the same time don't want to sacrifice one bit of our current lifestyle. The money, or will, when needed, is there.

    The world population already grew out of control. I mean it, in forty years we will probably see horses back on farmers' fields. The food production will drop by at least 50% in the western world, and we will not even know how to transport food to the consumer. And since virtually everybody will have the same problem, we'll witness massive starvation throughout the world. Worst case, also in the western worlds. Why would I care about a 'small' tax problem, considering that scenario?

    (The above is guesswork, I admit that. But everything considering agriculture is driven by oil, even in third world nations. The transportation, production, fertilization, packaging, cleaning, etc. Everything.)
    Last edited by a moderator: Oct 5, 2011
  19. Oct 5, 2011 #18
    A bit more elaborative. Next time you order a meal at a restaurant, consider the whole supply chain, and the role of oil in that. The waiter who arrived in his car, the gas used to cook the meal, the meal which was shipped over thousands of miles, the plastic packaging of the meal before it was prepared, the fertilizer produced from oil, the parts of the tractor -or other machinery- used in production, the pesticides shipped and prepared, the amount of labor in agriculture mechanized by fossil fuels, etc., etc., etc.

    Now imagine substantial parts of that supply chain breaking down. Do you think we are anywhere near prepared for a transition? It will be solved, eventually. But it's gonna be a quite 'dirty' transition.
  20. Oct 6, 2011 #19
    Then it stands to reason if the U.S. has 300 million people, we'll fare much better than if we had 500 million, right?

    Then you failed to answer the poll correctly. It asked what you thought was optimal, not what you think is most likely to happen.

    Who else answered 500 million or 1.2 Billion because they thought that's where we'd eventually be, rather than because they truly believe it's optimal? If so, you skewed the poll.
  21. Oct 6, 2011 #20
    Yeah, I think so. You need a population which is sustainable with agriculture and trade.

    I want to back down on this thread a bit. Maybe I am totally wrong, we'll witness a gradual decline of oil of several decades, a spike in food prices, and farmers which will get filthy rich producing enormous amounts of food in a novel manner with fuel-cell driven tractors. History is a bit against me, but that can happen too. The will is there, and we have enormously complex and dynamic economies, so it may not be as gloomy as I predict.

    Still, I personally think somewhere in between 200-300 million for the US is best.
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