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  THIS

Think of it this way.  We'll soon replace humans as operators of machines.  That's easy.  So any machine (aircraft, truck, tank, bulldozer, forklift, etc) which is currently operated by a human, will be automated, probably before mid-century.  

Humans that are in roles not currently mechanized or automated will take longer to replace.    

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Automating the operation is pretty easy, automating the maintenance is not.  Our forward maintenance footprint for something like reaper or global hawk is no smaller than for their manned counterparts.

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  Those would be the humans in roles which are not currently mechanized or automated.  

But two factors will eliminate even those jobs as well.  First, the technology will become more robust and efficient, requiring fewer and fewer people over time.  Once upon a time it took dozens of technicians to operate and maintain room sized computers that don't have the capabilities of the device on which you are accessing this forum.  Second, sometime over the next couple of decades we'll have our first general purpose robots.  Sometime later these general purpose robots will be advanced enough to replace many, if not most, roles currently preformed by humans.

Moore's law has held up since he first postulated it back in the 1960's.  If this 18 month exponential growth continues we'll replace humans this century.  The problem with technology is you go along for quite some time where nothing seems to be happening, or no real progress is being made (we don't have flying cars!).  And then just about the time you're about to give up on the idea, you're done.  

Here's a great explanation of how it works.  

"...Suppose it's 1940 and Lake Michigan has (somehow) been emptied. Your job is to fill it up using the following rule: To start off, you can add one fluid ounce of water to the lake bed. Eighteen months later, you can add two. In another 18 months, you can add four ounces. And so on. Obviously this is going to take a while.
By 1950, you have added around a gallon of water. But you keep soldiering on. By 1960, you have a bit more than 150 gallons. By 1970, you have 16,000 gallons, about as much as an average suburban swimming pool.

At this point it's been 30 years, and even though 16,000 gallons is a fair amount of water, it's nothing compared to the size of Lake Michigan. To the naked eye you've made no progress at all.

So let's skip all the way ahead to 2000. Still nothing. You have—maybe—a slight sheen on the lake floor. How about 2010? You have a few inches of water here and there. This is ridiculous. It's now been 70 years and you still don't have enough water to float a goldfish. Surely this task is futile?

But wait. Just as you're about to give up, things suddenly change. By 2020, you have about 40 feet of water. And by 2025 you're done. After 70 years you had nothing. Fifteen years later, the job was finished..."


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