Frankly @Kitteh_On_A_Cloud, if you worry about the future in the scope of hundreds of years or even longer, then overpopulation is the least of humanity's problems. The problem isn't so much overpopulation on a global scale, but uncontrolled population explosion in parts of the world where essential resources like food and water are already stretched (India and Yemen are good examples). Europe and North America could easily solve Africa and India's food shortages, but for various political and economic reasons, as @booinyoureyes pointed out, (literally) mountains of food are deliberately allowed to waste away rather than transported to needy parts of the world.
That said, @booinyoureyes's forecast is also over-optimistic. There is a physical limit to the earth's resources. New technologies can allow us to exploit them ever more efficiently, but there is a limit to how many human beings the planet can sustain, at a reasonable standard of living.
The argument that "population growth is good" is partly driven by capitalist economic theory, which promotes India's population profile as an advantage over that of China, where the One Child Policy will cause a significant population decline and ageing in the decades to come. However, capitalism only cares about profit, efficiency and factors of production, and the fact that the average Chinese citizen (barring unforeseen cataclysms) enjoy and will enjoy a much higher standard of living than their Indian counterparts, is irrelevant.
I can only say I got a very controversial point of view on this: If it weren't for wars, natural disasters and diseases, humanity would only overbreed and our planet would have to succumb to it in the end. We're already with almost 7 billion (!) people on this planet. And natural deaths get postponed more and more as technology evolves. China already has a one child law. Of course wars and such are horrible things, but in some way, they are necessary.
I feel I must refute some of the inaccuracies in the above quote. Firstly, although people die in wars, plagues and natural disasters, the main constraint on long term population growth is food availability. For example the Chinese Song Dynasty was almost perpetually at war with northern nomad empires like the Khitans, the Jurchens and the Mongols, the Chinese heartlands were repeatedly devastated and millions perished, but there was actually a major population explosion in China during the Song Dynasty, thanks to improvements in rice farming in southern China. In contrast, for the centuries of the Chinese Golden Ages of the Han Dynasty and Tang Dynasty, where the Chinese heartland was untouched by major strife, the population was relatively stable, but did not grow, because the land could only support so many people anyway.
My point is that population growth would never occur to an extent where "our planet would succumb to it in the end". Populations are constantly limited by the availability of food and water, and inter-communal strife (or civil war) is often just a symptom of resource stresses. Plagues and war might wipe out half the world's population, and introduce major population shocks, but in the long run it provides opportunity for the next generation to replace them. (I am ignoring some sort of cataclysm where the planet is left inhospitable).
Finally war is never "necessary". It doesn't even have that much of an impact on population, unless we finally go thermonuclear in a major way. In most wars, more people die as a result of famine and disease than actual violence. For example retreating armies often use scorched earth tactics and burn crops entire villages and towns to deny their enemy food and shelter. That makes sense strategically, but what about all the people who relied on that farmland?... Unlucky.
Due to logistical constraints, very few armies in the pre-modern era could carry sufficient food to support themselves for a long campaign, and the standard practise was to seize what they needed from towns and villages they passed by, so even if an army did not intentionally destroy crops, civilians in an affected area are often screwed anyway.
All in all, war is almost always a terrible tragedy that causes unnecessary and enormous human suffering.
War is necessary to change the world and move mankind forwards. For example, without the American civil war slavery wouldn't have been abolished so fast; without WW2 the world wouldn't have recovered from the great depression so fast; without the cold war people today wouldn't just blindly believe in capitalism even when it is against their interests.
War is a terrible tragedy multiplied many million times over. There is a memorial in the town center of every single town and village here in Britain, to remember these who died in WW1 and WW2. Each of the names on those rocks is a tragic story of loss. They deaths made our world what is it today.
War between nation states is driven by the ambitions of a few old men. What conflict of interest is there between a Russian living in Moscow, a German living in Berlin, and a Ukrainian living in Kiev? Do they want the farm land or cattle the other guy has? No. Do they want to loot and kill because they have no food to eat? No. So why would a Russian kill an Ukrainian?
I'm surprise by the warmongering stance of Russia. Didn't they used to teach Marxism in the Soviet Union? Don't they know the futility of war between nation states? Don't they know that a Russian person and an Ukrainian person have far more in common with each other than they have with the leaders of either country? The Russian in Moscow and the Ukrainian in Kiev both want food, shelter, meaningful work, family, community, entertainment, justice, freedom from fear and oppression. They do not have conflict of interest with each other, they have conflict of interest with their own government and economic systems. This is the meaning of "Proletarians of all countries, unite! You have nothing to loose but your chains". It's not just a pretty slogan, it's a practical solution to an international problem. In the squares of Moscow and Kiev, we need more people waving Soviet flags and less people waving Russian and Ukrainian flags, that will resolve the heart of this problem.
without WW2 the world wouldn't have recovered from the great depression so fast
This is such a horrible myth. People need to understand that economics is the study of how individuals and organizations manage scarce resources. The way I see it a "good economy" is when these resources are used to fulfill peoples needs and wants. It is both moral and good for growth.
To expend these resources on destruction seems to be the complete opposite of what I and many others would consider to be a "good economy". The resources that are going toward tanks and guns are now unavailable for use for things people want and need, like products that simplify everyday activities, items that ensure their safety or things that entertain. This does not seem to be the best method of managing scarce resources.
Of course war is occasionally necessary (WWII is a good example). However, to say that the war led to economic recovery is not true if you examine what actually occurred in the home front of most nations involved in the conflict. You should ask your grandparents about candy rationing in England during the 40s (and candy is the least of the problem, just the one that got a lot of coverage due to involving children). Very similar limitations were put on Americans as well, with everything from sugar to oil being rationed.
Personal austerity is not a sign of a healthy economy. Also, full employment isn't much of an accomplishment when there is forced conscription.
Yet economic costs don't even compare to the human costs.
Also about the American Civil War, I think this is also a bit of a myth. Every nation in the West other than the US and Haiti eliminated the institution of slavery without conflict. The political realities of the time may have called for it, but it was far from necessary. The result of slavery being ended in the US (which actually didn't occur until about a decade after the end of the war) was great and a monumental moment in American history, but the cost in lives was also horrible. A good outcome does not always mean that there were not better alternatives.
Robots are currently searching for water on Mars. Why do you think that is? Because water is precious, as only 2% of the water available is usable and consumable. The rest is salt water which can practically only be used for fishing and gaining salt.
This is just incredibly inaccurate I mean come on... the reason they are searching for water is because it is a sign of life. I think its kind of weird to think that we will find a way to extract water from a different inhospitable planet and transport it to the Earth in large quantities before we discover technology that makes desalination cheap and easy (we are already on the brink. Lockheed Martin of all companies has actually come up with a great method). I really doubt that people at NASA think that tapping into off-planet resources is smarter than developing the technology needed to make the most of what is already easily accessible.
I could be wrong, and I'll eat my word if I am, but if we find a way to colonize Mars and move a significant portion of the population there before we can convert salt water into drinking water then I am a bearded gnome (and I'm clean shaven)!
A good outcome does not always mean that there were not better alternatives.
Yes, war occurs when there are no better alternatives. Continuing with the same 2 examples:
Without American civil war, would the southern states have voluntarily given up their entire labour force and ruined their plantation based economy for the sake of an ideal? After the war the southern states suffered the longest period of economic depression, which they didn't recover from until the 20th century. This depression has been blamed on the war itself, because to blame it on the end of slavery would be racist and contradict the winds of "political correctness". The fastest way to recover from that war would have been a massive import of slaves to replace the lost manpower.
Without WW2, the massive unemployment, the contraction of private credit and the resulting decrease in economic activity would have continued. How can you get people to spend money when the economy is bad and getting worse? How can you get banks and big companies to invest in enterprises and projects when the risk of default in high and increasing (because the demand for goods is decreasing)? The common solution used by Hitler and Roosevelt was to increase government spending on big public works projects; the difference between Hitler and Roosevelt was Hitler went one step further and invaded Poland.
That brings us onto a very interesting point. Why did pre-WW2 Germany want "living space"? and Why did pre-WW2 Japan want "East Asian co-prosperity sphere"? The answer is very simple: Germany and Japan were both rising industrial powers that needed secure imports of raw resources and large markets to consume their exports. With British Empire, America, Soviet Union, French Empire, Dutch Empire, controlling the majority of the world, and these A-B-C-D powers of the established world order excluding the new players of Germany and Japan, there was no alternative except war. And you know what? The war achieved the objectives of (West) Germany and Japan. The empires disintegrated, world wide markets developed, and they were allowed into the "free world".
Looking into the future, what is America, British common wealth, EU, Russia and Japan doing about the rising industrial power of China? It would be a real tragedy if the cause of WW3 is the same as the cause of WW2.
I thought I'd add a couple of comments about WWII and desalination, disparate topics though they are.
The Second World War was an economic boon to the USA, as they were able to export huge amounts of food, arms and other products to the Allied nations - a profitable trade surplus. Combined with high rates of employment in these industries and the military there was the ability to economically recover and prosper during the war and immediate aftermath. The G.I. bill and Baby boom were the result, and something of a prosperous golden age began - in the US. At the end of WWII the US had about half the world's total industrial output.
Much of the rest of the world was in a very different situation. As @booinyoureyes accurately says, there was still rationing in Britain until 1954. My dad remembers it. Meat, milk, cheese, sugar and sweets were all rationed post-war. Despite the setup of the National Health Service there wasn't much money to go around. It's been called "an Age of Austerity". Debt to the US didn't help (finally repaid fully in 2006). The 1950s saw a return of prosperity to the UK, not WWII.
The USSR was completely gutted by the war. 40 million deaths and the complete destruction of several major cities did not help the economy. There was postwar economic recovery, but focused on heavy industry to the detriment of agriculture and other sectors. And these are the countries that won WWII.
There was unrest and war as consequences of WWII for decades. The Independence (& Partition) of India was a condition of US help to the British Empire: 3 million dead. Greece was torn by civil war. Many European countries were either either split or absorbed by what Churchill described as "an Iron Curtain". West Germany (as with much of Europe) had been ravaged by war and only US assistance to prevent the spread of Communism rebuilt it into a thriving nation.
The perception is often that WWII ended the Great Depression, and it did for the US. But it brought about ongoing hardship, starvation, destruction and misery to much of the world, including the victors.
As for water - a search for water on Mars is more likely to seek evidence of life, or possibly as a source to sustain small-scale exploration in future. Water essential to terrestrial life, but also a source of hydrogen and oxygen for fuel cells. It would be much easier to harvest extraterrestrial water from asteroid mining, and avoid having to overcome Mars' gravity, than to extract it from Mars.
Much of the world has little problem obtaining adequate fresh water for drinking, some dry developing countries being the exeption. The challenge is the large amounts of potable water needed for agriculture. There have been a few proposals to overcome this, including solar desalination and greenhouse agriculture in deserts located near seawater. There is a project I'm aware of in the Australian Outback that is trying to do just this.
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That said, @booinyoureyes's forecast is also over-optimistic. There is a physical limit to the earth's resources. New technologies can allow us to exploit them ever more efficiently, but there is a limit to how many human beings the planet can sustain, at a reasonable standard of living.
The argument that "population growth is good" is partly driven by capitalist economic theory, which promotes India's population profile as an advantage over that of China, where the One Child Policy will cause a significant population decline and ageing in the decades to come. However, capitalism only cares about profit, efficiency and factors of production, and the fact that the average Chinese citizen (barring unforeseen cataclysms) enjoy and will enjoy a much higher standard of living than their Indian counterparts, is irrelevant. I feel I must refute some of the inaccuracies in the above quote. Firstly, although people die in wars, plagues and natural disasters, the main constraint on long term population growth is food availability. For example the Chinese Song Dynasty was almost perpetually at war with northern nomad empires like the Khitans, the Jurchens and the Mongols, the Chinese heartlands were repeatedly devastated and millions perished, but there was actually a major population explosion in China during the Song Dynasty, thanks to improvements in rice farming in southern China. In contrast, for the centuries of the Chinese Golden Ages of the Han Dynasty and Tang Dynasty, where the Chinese heartland was untouched by major strife, the population was relatively stable, but did not grow, because the land could only support so many people anyway.
My point is that population growth would never occur to an extent where "our planet would succumb to it in the end". Populations are constantly limited by the availability of food and water, and inter-communal strife (or civil war) is often just a symptom of resource stresses. Plagues and war might wipe out half the world's population, and introduce major population shocks, but in the long run it provides opportunity for the next generation to replace them. (I am ignoring some sort of cataclysm where the planet is left inhospitable).
Finally war is never "necessary". It doesn't even have that much of an impact on population, unless we finally go thermonuclear in a major way. In most wars, more people die as a result of famine and disease than actual violence. For example retreating armies often use scorched earth tactics and burn crops entire villages and towns to deny their enemy food and shelter. That makes sense strategically, but what about all the people who relied on that farmland?... Unlucky.
Due to logistical constraints, very few armies in the pre-modern era could carry sufficient food to support themselves for a long campaign, and the standard practise was to seize what they needed from towns and villages they passed by, so even if an army did not intentionally destroy crops, civilians in an affected area are often screwed anyway.
All in all, war is almost always a terrible tragedy that causes unnecessary and enormous human suffering.
War is a terrible tragedy multiplied many million times over. There is a memorial in the town center of every single town and village here in Britain, to remember these who died in WW1 and WW2. Each of the names on those rocks is a tragic story of loss. They deaths made our world what is it today.
War between nation states is driven by the ambitions of a few old men. What conflict of interest is there between a Russian living in Moscow, a German living in Berlin, and a Ukrainian living in Kiev? Do they want the farm land or cattle the other guy has? No. Do they want to loot and kill because they have no food to eat? No. So why would a Russian kill an Ukrainian?
I'm surprise by the warmongering stance of Russia. Didn't they used to teach Marxism in the Soviet Union? Don't they know the futility of war between nation states? Don't they know that a Russian person and an Ukrainian person have far more in common with each other than they have with the leaders of either country? The Russian in Moscow and the Ukrainian in Kiev both want food, shelter, meaningful work, family, community, entertainment, justice, freedom from fear and oppression. They do not have conflict of interest with each other, they have conflict of interest with their own government and economic systems. This is the meaning of "Proletarians of all countries, unite! You have nothing to loose but your chains". It's not just a pretty slogan, it's a practical solution to an international problem. In the squares of Moscow and Kiev, we need more people waving Soviet flags and less people waving Russian and Ukrainian flags, that will resolve the heart of this problem.
To expend these resources on destruction seems to be the complete opposite of what I and many others would consider to be a "good economy". The resources that are going toward tanks and guns are now unavailable for use for things people want and need, like products that simplify everyday activities, items that ensure their safety or things that entertain. This does not seem to be the best method of managing scarce resources.
Of course war is occasionally necessary (WWII is a good example). However, to say that the war led to economic recovery is not true if you examine what actually occurred in the home front of most nations involved in the conflict. You should ask your grandparents about candy rationing in England during the 40s (and candy is the least of the problem, just the one that got a lot of coverage due to involving children). Very similar limitations were put on Americans as well, with everything from sugar to oil being rationed.
Personal austerity is not a sign of a healthy economy. Also, full employment isn't much of an accomplishment when there is forced conscription.
Yet economic costs don't even compare to the human costs.
Also about the American Civil War, I think this is also a bit of a myth. Every nation in the West other than the US and Haiti eliminated the institution of slavery without conflict. The political realities of the time may have called for it, but it was far from necessary. The result of slavery being ended in the US (which actually didn't occur until about a decade after the end of the war) was great and a monumental moment in American history, but the cost in lives was also horrible. A good outcome does not always mean that there were not better alternatives.
I could be wrong, and I'll eat my word if I am, but if we find a way to colonize Mars and move a significant portion of the population there before we can convert salt water into drinking water then I am a bearded gnome (and I'm clean shaven)!
Without American civil war, would the southern states have voluntarily given up their entire labour force and ruined their plantation based economy for the sake of an ideal? After the war the southern states suffered the longest period of economic depression, which they didn't recover from until the 20th century. This depression has been blamed on the war itself, because to blame it on the end of slavery would be racist and contradict the winds of "political correctness". The fastest way to recover from that war would have been a massive import of slaves to replace the lost manpower.
Without WW2, the massive unemployment, the contraction of private credit and the resulting decrease in economic activity would have continued. How can you get people to spend money when the economy is bad and getting worse? How can you get banks and big companies to invest in enterprises and projects when the risk of default in high and increasing (because the demand for goods is decreasing)? The common solution used by Hitler and Roosevelt was to increase government spending on big public works projects; the difference between Hitler and Roosevelt was Hitler went one step further and invaded Poland.
That brings us onto a very interesting point. Why did pre-WW2 Germany want "living space"? and Why did pre-WW2 Japan want "East Asian co-prosperity sphere"? The answer is very simple: Germany and Japan were both rising industrial powers that needed secure imports of raw resources and large markets to consume their exports. With British Empire, America, Soviet Union, French Empire, Dutch Empire, controlling the majority of the world, and these A-B-C-D powers of the established world order excluding the new players of Germany and Japan, there was no alternative except war. And you know what? The war achieved the objectives of (West) Germany and Japan. The empires disintegrated, world wide markets developed, and they were allowed into the "free world".
Looking into the future, what is America, British common wealth, EU, Russia and Japan doing about the rising industrial power of China? It would be a real tragedy if the cause of WW3 is the same as the cause of WW2.
The Second World War was an economic boon to the USA, as they were able to export huge amounts of food, arms and other products to the Allied nations - a profitable trade surplus. Combined with high rates of employment in these industries and the military there was the ability to economically recover and prosper during the war and immediate aftermath. The G.I. bill and Baby boom were the result, and something of a prosperous golden age began - in the US. At the end of WWII the US had about half the world's total industrial output.
Much of the rest of the world was in a very different situation. As @booinyoureyes accurately says, there was still rationing in Britain until 1954. My dad remembers it. Meat, milk, cheese, sugar and sweets were all rationed post-war. Despite the setup of the National Health Service there wasn't much money to go around. It's been called "an Age of Austerity". Debt to the US didn't help (finally repaid fully in 2006). The 1950s saw a return of prosperity to the UK, not WWII.
The USSR was completely gutted by the war. 40 million deaths and the complete destruction of several major cities did not help the economy. There was postwar economic recovery, but focused on heavy industry to the detriment of agriculture and other sectors. And these are the countries that won WWII.
There was unrest and war as consequences of WWII for decades. The Independence (& Partition) of India was a condition of US help to the British Empire: 3 million dead. Greece was torn by civil war. Many European countries were either either split or absorbed by what Churchill described as "an Iron Curtain". West Germany (as with much of Europe) had been ravaged by war and only US assistance to prevent the spread of Communism rebuilt it into a thriving nation.
The perception is often that WWII ended the Great Depression, and it did for the US. But it brought about ongoing hardship, starvation, destruction and misery to much of the world, including the victors.
As for water - a search for water on Mars is more likely to seek evidence of life, or possibly as a source to sustain small-scale exploration in future. Water essential to terrestrial life, but also a source of hydrogen and oxygen for fuel cells. It would be much easier to harvest extraterrestrial water from asteroid mining, and avoid having to overcome Mars' gravity, than to extract it from Mars.
Much of the world has little problem obtaining adequate fresh water for drinking, some dry developing countries being the exeption. The challenge is the large amounts of potable water needed for agriculture. There have been a few proposals to overcome this, including solar desalination and greenhouse agriculture in deserts located near seawater. There is a project I'm aware of in the Australian Outback that is trying to do just this.
A couple of interesting links:
http://en.wikipedia.org/wiki/Planetary_Resources - a company that proposes to mine asteroids, Google's Executive Chairman is an investor.
http://www.theguardian.com/environment/2012/nov/24/growing-food-in-the-desert-crisis - Guardian article about solar desalination & agriculture.