I wish I could find the article which described this. If I recall, the railgun was supposed to be enormous and would be miles in diameter.

Perhaps one of the big benefits of a naval railgun is that it's so difficult to defend against. Old-fashioned anti-ship missiles can be disabled or destroyed by the defending ship's close-in defenses. This is because the incoming missile is filled with sensitive electronics, guidance systems, explosives, fuel, turbojet engines, stabilizing fins, etc, and is very likely to be damaged or destroyed if hit by a 20mm round from the defending ship's CIWS missile defenses.

However, how do you shoot down a hunk of metal traveling at mach 7 toward your ship? It wouldn't make any difference if you hit it with a 20mm round from the goalkeeper or phalanx. The projectile would just keep flying toward the ship and strike it anyways. Besides, how would you even hit something which is so small and traveling at mach 7.

It doesn't seem there would be any good defense against this.

I recall a proposal (at this point very hypothetical) to have a huge railgun arranged in a loop, which would be situated somewhere in the continental US. The projectile would go around and around in the railgun loop, accelerating each time, like a slingshot, until it's flung out toward the target. The projectiles would go so fast that they'd fly out into orbit before coming back down. This would allow us to "shell" any country on earth from some railgun in the US. The "shells" in this case would have so much kinetic energy that they'd level a city block from the shock wave they'd create upon landing.

WHY DON'T WE HAVE THIS ALREADY? It's the ultimate homeland defense.

I enjoy it so much when people with such immature points make such obvious errors in spelling and grammar. Please tell me more about my "inanity" and "muppetude" man, you are like a rocket scientist with your magical cognitive abilities.

Before you criticize others' grammar, you should learn the difference between a comma and a period. Most people had mastered that by the 3rd grade. You, on the other hand, didn't manage to put together two sentences without making childlike mistakes.

John gets polio and you do not, there is no issue.

I don't know whether to laugh or cry. You can't even write at the 3rd grade level.

You do know what a false dilemma is don't you?

The poster hadn't committed the false dilemma fallacy. Look it up, and figure out what it means.

You're just an utter idiot, over and over again.

I think the model wrongly assumes that elites draw down essential resources faster than commoners. In pre-modern society, that appears to have been incorrect. In pre-modern civilizations, it was over-farming and the reduction in soil fertility which was subject to draw-down, and not "resources" more generally. (For example, there is reasonably good evidence that soil degradation contributed to the collapse of the western roman empire). Elites do not consume much more food than commoners. As a result, I'm not sure it would make any different how stratified society is. Take the chateaux of the Loire Valley as an example: they're extravagant, but they're not built out of materials (such as stone) which became exhausted anywhere or threatened civilization.

In pre-modern societies, elites subsisted off the surplus labor which was left over after commoners had provided for their own subsistence. According to best estimates, this "surplus" labor available for exploitation by elites was never more than 20% of the total commoner labor available. Most labor in pre-modern societies was used in simply providing enough food for everyone to survive. In ancient Egypt, more than 90% of the population spent all their working time devoted to agriculture or household work, and similar ratios existed in other civilizations. As a result, the total consumption of elites in pre-modern society was never a large fraction of the total production of society. Some elites may have had extremely extravagant lifestyles compared to commoners, but that is because such elites' numbers were extremely small, generally much less than 1% of the population.

Another important consideration here is the difference between reduction of population, and the collapse of some political order. Insofar as I can tell, soil degradation often leads to a gradual reduction in population over centuries until some political order suddenly cannot be sustained. Often, ancient civilizations were empires in which some center had a large army and long transportation networks. The empire dominated a group of subject peoples on the periphery, and extracted the products of their surplus labor beyond subsistence and transported those surplus products to the center. Usually, the subject peoples disliked being so dominated. It seems possible to me that soil degradation could lead to a reduction in the size of the surplus, and thus the size and power of the army of the empire, until the arrangement suddenly could not be maintained. Take the western roman empire as an example: soil degradation and population decline had been happening for centuries, until the army weakened and a barbarian tribe invaded and suddenly overran and destroyed the empire.

Of course, the main criticism of the paper is that it's wildly speculative. There is no data whatsoever in the paper. This is excusable because there is very little "data" in the modern sense left over from pre-modern civilizations. Pre-modern peoples were extremely good at telling stories and writing epics, but poor at keeping records and statistics of commoners' well-being. For this reason, and other reasons, the causes of the collapses of many civilizations (such as the meso-American civilizations) are not well understood, and the explanations are highly speculative and different from each other. Many researchers speculate that the American civilizations collapsed because of long-lasting mega-droughts, which obviously would not fit this model of resource draw-down.

Usually, when constructing a model, it's at least necessary to verify that the model agrees with past evidence. Even then, the model may not be predictive at all; however, constructing a model which agrees with past evidence is often a first step. Unfortunately, the model in this case is just wildly speculative. There are virtually no examples of egalitarian civilizations prior to the 18th century, and so no data on how egalitarian civilizations would have fared. There is no data on soil fertility, consumption by elites, resource draw-down, total populations of civilizations, etc, which this model refers to. Instead, the model is along the lines of "this seems plausible".

If you had no assumptions of my political affiliation, then your remarks about cognitive dissonance make no sense.

Or maybe white people only care when other white people are killed in high concentrations. But that wouldn't fit your partisan philosophy.

Except the Soviet Union, which I mentioned, consisted of other white people. Also, the issue wasn't just that white people "didn't care"; the problem was that some white people explicitly denied that the massacres had occurred. It's not a matter of them just not caring.

Cognitive dissonance is a human trait. You are engaging in it yourself when you try to cast the left as engaging in it more than the right... Your whole argument is itself simply an expression of a double standard when you try to claim the left engages in this more than the right.

You wrongly guessed my political affiliation. I have never voted Republican in my life. Furthermore, I was voted most liberal by my graduating high school class in San Francisco.

Whole Foods is treated differently because of the moral and intellectual double standards which prevail on the left. Leftists and rightists both treat things differently when they are done by people on "our side" and so practice double standards. The left, however, is particularly bad in that regard.

One example of this was the extremely widespread holocaust denial (or something akin to holocaust denial) which is rampant on the left and has always been. I am not talking about the mass murder in Germany. I am referring to the mass murder in the Soviet Union in the 1930s through the 1950s and even after; the mass murder in Cambodia in the 1970s; and the ongoing mass murder and severe political repression in almost all explicitly "socialist" countries which until recently were the darlings of far leftists everywhere. Those mass murders were denied or disputed by considerable numbers on the left. What's more, the denial of mass murder is ignored by a great many other leftists who do not deny that those murders occurred. There is a double standard. Whereas most leftists would vehemently protest (and rightly so) when someone disputes the Holocaust, they are strangely silent when one of their own disputes the mass killings of leftist regimes.

The denial was especially severe with regard to Cambodia. The Khmer Rouge murdered 1/4th of the population of that country within a few years. A whole industry of professors and leftist figures exist to deny the mass-murder there. Even Noam Chomsky tried hard to deny the killing fields, and tried hard to dispute the reports of massacre emanating from that country. The reason for this denial (I suspect) is because the mass murders followed a socialist revolution and were orchestrated by far leftists who had been educated in Paris, and who had been supported enthusiastically by the far left. The fact that it resulted in mass murder is difficult to accept for people who are convinced of their own ethical superiority. Thus, a double standard evolved.

If Noam Chomsky had been a Nazi sympathizer and had denied the Holocaust, he would be a forgotten figure by now, as he deserves to be, for various reasons. However, he spent his time denying the mass murder in Cambodia, so it was forgotten.

These double standards prevail everywhere. My leftist friends cannot stop laughing at young earth creationism, but are in thrall to pseudoscientific nonsense which makes creationism look sophisticated in comparison. There are all kinds of T-Shirts meant to mock creationism, with a "Teach the Controversy" byline beneath a Triceratops attached to a plow. There are not, however, T-Shirts worn by my leftist friends mocking homeopathy, or all kinds of ancient medical quackery, or "energy medicine", or "multiple chemical sensitivity", or the recent widespread belief that vaccines are dangerous and aren't worth it. Granted, these things are not practiced by most people on the left. However, they are ignored by people on the left who have a scientific understanding, who reserve their vitriol for the pseudoscience of the other side.

There are also double standards with regard to doomsday groups. Each side of the political spectrum mocks the doomsday groups of the other side. People who are waiting for "the end times" are mocked by those on the left. However, peak oiler doomers (almost all of whom were on the far left) who assured us that civilization certainly would collapse before 2008 are largely exempt from that mockery.

I suppose double standards are easy to fall into. It's difficult to condemn one of your own.

But other than piloting, what else do humans do, and how automatable is it?

Generally the employees on a ship are divided into officers and crew. The officers include the captain, first mate, and second mate. Also the officers include the engineering department, with a chief engineer, second engineer, and third engineer. Among the crew, there are a bunch of seamen (perhaps 5 or more of them). There is also a steward and a cook.

All of these people are divided into shifts. At any given time, there are 5 or so people working: one deck officer (such as the captain), one engineer (who is maintaining the large engine), and a couple of able seaman, one of whom is on lookout at the front of the ship.

I doubt they could do away with the engineering positions. These ships have large engines which require continuous maintenance. It won't be done by robots any time soon.

Perhaps they could automate the captain/lookout positions. Doing so would reduce the people on a shift from 5 or so, to 3. Perhaps there could be one captain for a convoy of ships, and a single lookout for the forward-most ship in the convoy. Also they could reduce the steward/cook to one person (instead of two) per ship in that case.

In the article they say that drone ships will eventually be commanded by captains on the land.

However, the article includes a CGI picture of a convoy of containerships. I'm guessing the idea might be to have a convoy of drone ships, where a single captain controls 6 different ships in a convoy. Maybe that would be the first iteration, with land-based control coming later.

I should also point out that the statistics mentioned in the article are incorrect. From the article:

Crew costs of $3,299 a day account for about 44 percent of total operating expenses for a large container ship, according to Moore Stephens LLP, an industry accountant and consultant.

A modern containership can cost $200 million, and can consume 300 tons of bunker fuel per day. Thus, the fuel costs are over $100,000 per day, and the costs of the purchase of the ship are over $50,000 per day.

Thus, crew costs are more like 2% of all costs, and not 44% as the quotation indicates.

The only way to arrive at the 44% figure is if you break down containership costs into capital costs (the cost of the ship), bunker costs (fuel), and operating costs (not including fuel). This kind of breakdown is commonly done. If you break things down in this way, "operating costs" are generally about 10% of the total cost of running the ship, and labor costs would be 44% of that ~10%. Thus, labor costs altogether are a few percent of the cost of running a ship.

The article does not spell this out, and gives a mistaken impression.

Drone ships would have very little benefit compared to ships of today, and would save very little labor. That's because crew sizes are already negligible on modern ships. Ships require very little labor for their operation. For example, a massive containership like the Maersk Triple-E might carry 15,000 containers (equivalent to about 7,000 tractor-trailer truckloads) while having a crew of 15, in three shifts. At any one time, there are 5 people transporting 7,000 tractor-trailer truckloads of cargo. If we reduced those jobs, it would make very little difference to costs or anything else.

Bear in mind that three of the 15 positions are the engineering staff who are frequently performing physical operations on a massive engine. Those jobs will not go away by having a single captain for multiple ships.

The number of jobs on a ship is decreasing every year anyway, as ships gradually grow larger. Larger ships generally do not have larger crews, so the amount of labor per unit of cargo keeps dropping anyway. Large containerships today carry more than twice the cargo of ships from 20 years ago, while crew sizes have not grown, so the amount of labor per unit of cargo has dropped by half and continues dropping.

Labor costs are already an extremely small fraction of the costs of operating a ship. It would make little difference to reduce labor costs further.

Your comment is incoherent.

working to turn both genders feral for the sake of ego-driven identity politics/ideology or profit motive.

How is the profit motive turning both genders "feral"? The profit motive may well be repellent, at least to some, but it certainly doesn't do that.

How is identity politics turning both genders "feral"? It doesn't seem to me that untamed animals participate in identity politics or were made that way by identity politics, or that anyone has ever been made "feral" by identity politics.

Of course, the term "identity politics" is a mostly a derisive way of saying "minority rights", and especially rights for women. However it's difficult to say outright that you oppose rights for certain groups of people. Thus it was necessary to create a bad-sounding term, in order to make the insistence upon rights sound petty or (in your words) "ego-driven".

I wish you luck if you live in the west. You'll need it.

I doubt he will need luck living in the west.

Whoops. The post got garbled because slashdot wrongly interpreted the less-than sign as an html tag opening, and I didn't escape it. (Which seems like a bug to me. The text "p<0.05" is obviously not the beginning of an html tag, because no html tags accepted by slashdot begin with 0.05). Anyway, the offending paragraph should say:

Then something interesting happened. The original researcher responded by looking for subsets of the data from the large study, to find any sub-groups where his hypothesis would be confirmed. He ended up retorting that "keeping a positive mental outlook DID work, according to your own data, for 35-45 year-old east asian females (p<0.05)"... How many statistical tests did he perform to reach that conclusion, while trying to rescue his hypothesis? If he ran more than 20 tests, then you would expect one spurious positive result just from random error, even though his p value was less than 0.05.