I hope you're ready for a wall of text. Had to break this into multiple posts...
I have several comments about what you're proposing, to the extent that I understand it.
> I think that every adult US citizen should get an annual share of the US GDP.
Right of the bat, you're starting with GDP, which is an inherently flawed measure of economic output. Namely, it gets imports and exports backwards. If you want to distribute incomes to people, it would be useful for the amount of the incomes to somehow line up roughly with the amount of stuff they'd able to buy with those incomes. The higher the potential imports, the more people can potentially buy.
As a thought experiment, we can imagine that foreign countries are analogous to firms that don't use any labor to produce what they produce. The output of the firms, of course, adds to total GDP. And the output of the countries subtracts from total GDP. This is despite the fact that the two are the same thing.
I've written a blog post about this: http://www.suncho.com/blog/20170616_gdp_is_wrong.html
> I believe that owning something like a share in America would align all of us in making the country as successful as possible
No. It wouldn't. The problem here is that you run into the tragedy of the commons. Everyone receives the benefit whether they happen to be contributing or not. This creates an incentive not to contribute because you're going to receive the benefit anyway. This is why communism doesn't work.
The good news is that we by and large don't need most people to contribute. So an incentive not to contribute might not be such a bad thing.
> the better the country does, the better everyone does
Yes. But the good news is that you really don't need to incentivize people to be involved in making the country successful. The innovations of the few can benefit the many.
> give more people a fair shot at achieving the life they want.
The idea that people should have to "achieve" the life they want is a little silly. We have to resources to give everyone an amazing life without them having to work for it. We're operating way below our productive capacity.
There's a Buckminster Fuller quote that I really like:
"We must do away with the absolutely specious notion that everybody has to earn a living. It is a fact today that one in ten thousand of us can make a technological breakthrough capable of supporting all the rest."
Figuring out how to embrace joblessness as a positive force for humanity is probably the most important social challenge we currently face.
I also wrote a blog post about this: http://www.suncho.com/blog/20150326_morality.html
> And we all work together to create the system that generates so much prosperity.
As I've said, we really don't need everyone to be working together. Furthermore, even if you really want people to be working together, your plan to doesn't incentivize us to do that.
> I believe that a new social contract like what I’m suggesting here--where we agree to a floor and no ceiling--would lead to a huge increase in US prosperity and keep us in the global lead.
When we distribute money to people (e.g. through a basic income), there's always going to be an amount that's optimal for social prosperity. I agree with you that it would be a mistake to put a cap on the amount of the basic income that's below what's socially optimal. I cringe every time someone says that the basic income should be exactly equal to the amount that pays for everyone's basic needs.
But it would also be a mistake to put a floor on the basic income that's above what's socially optimal. That being said, I think we have enough available resources that the optimal amount of basic income would be well above what most of the "basic needs" people are calling for.
> Countries that concentrate wealth in a small number of families do worse over the long term--if we don’t take a radical step toward a fair, inclusive system, we will not be the leading country in the world for much longer. This would harm all Americans more than most realize.
I mostly agree. If we flatten out the aggregate demand curve by providing an evenly distributed income to everyone, then that increases quantities demanded of many of the things we produce and allows us to scale up production. This gives more people more access to more wealth.
> Today, the fundamental input to wealth generation isn’t farmland, but money and ideas--you really do need money to make money.
Hmm. Sort of. Even today there are resources we use that are factors of production that aren't farmland, but that are analogous to farmland. And we still have farmland, of course. Technological improvement allows us to use such resources more and more efficiently with time. Our overall productive capacity increases with time. We also have financial resources and we can certainly make money out of money.
But then another important factor is demand. We're not going to generate (i.e. produce) wealth if nobody's going to buy it. Our technology can improve all it wants, and our productive capacity can go through the roof. If people don't have the incomes to pay for all this stuff, it won't matter.
As far as ideas go, I'm not sure how important they are. Ideas are a dime a dozen. There are no new ideas on the face of the planet (except of course for my ideas, which are unique and special). Execution on ideas can be great. Innovation can be great. But as long as we're constrained by demand, none of that is going to help. Demand is our bottleneck. By focusing attention elsewhere, we're prematurely optimizing a part of the code that isn't going improve performance.
> American Equity would also cushion the transition from the jobs of today to the jobs of tomorrow.
Huh? Are you saying that if everyone had an income it would give them the freedom to work on things that are actually going to matter?
> Automation holds the promise of creating more abundance than we ever dreamed possible, but it’s going to significantly change how we think about work.
It depends on us significantly changing how we think about work.
> If everyone benefits more directly from economic growth, then it will be easier to move faster toward this better world.
Yes.
> The default case for automation is to concentrate wealth (and therefore power) in a tiny number of hands.
Yes. If we rely on wages for people's incomes and production is constrained by consumer spending levels, then the result of automation is necessarily a reduction the amount of wealth we produce. And the people who do have access the the wealth are the ones who somehow still have sufficient incomes to purchase it.
> America has repeatedly found ways to challenge this sort of concentration, and we need to do so again.
Yes. But it's been pretty ugly so far. A lot of it involves contorting the labor market in an attempt to get somewhere close providing people with sufficient incomes through wages. I hope we can do better in the future.