Look, guys, the reality is that 20, 30, maybe 50 years from now, a combination of increasing automation and population will leave the US without enough work for everyone to work a 40-hour week. You can try to pretend to yourselves that that's not true but you're wrong and that's really the end of that.
So if we're to keep a market economy (which I firmly believe we ought; it is by far and away the most efficient economic system mankind has ever developed), we will need to do something about the inexorable rise of structural unemployment. Here are our options:
1) Pursue a policy of limiting population growth: mandatory limits on the number of kids people are allowed to have, sharper immigration quotas, and forced emigration. None of these are remotely tasteful, ethical or effective. Limiting reproduction has disastrous long-term consequences for a society's age distribution, sharper immigration quotas will only increase the amount of illegal immigration into the country, and forced emigration is a nonstarter both morally and practically (granting the government the power to kick people out of the country in the name of economic vitality is a dangerous precedent, and realistically, people who are out of a job aren't going to leave the country, they'd more likely resort to crime to feed their families).
2) Expanding the current welfare state. The current welfare state is already unsustainable in the long-term as it is; any expansion to accommodate more people going on the public dole would only accelerate its inevitable collapse.
3) Doing nothing and letting those without work fend for themselves. What happens here is that the poor turn to crime to feed their families -- not because they're somehow morally deficient but because *they have no realistic alternative to survive*. And when crime goes up like that, you can either greatly expand the police force to keep people safe, or you can let people get robbed, burglarized, murdered, etc. The latter would lead to societal collapse and the former would rapidly accelerate and encourage the current trend of police militarization, ending notions of freedom as you know them... and on top of that, as more people end up in prison, either prison conditions become unlivable (in which case you've just empowered police to throw people in inhumane prisons as a means of saving your economy -- good one!) or prisons become too expensive to maintain (as they effectively replace welfare).
4) Recognize the inevitable failures of 1-3 and restructure your economy in line with the new technological reality. This means ending the increasingly flawed notion that one must hold down a job to be a successful person and a "good" member of society. I mean shit, this is the opposite of what capitalism is about. Socialism promotes the notion that everyone should be working and that it's all about labor, etc. etc. Capitalism is fundamentally about getting the most shit done with the fewest inputs, labor included. That irreconcilably clashes with the idea that you must work to be a good citizen. What if the efficient thing to do is to have some people not working, and to automate work they could do? Are they somehow lesser people or lesser members of society for it? Once you end that, all manner of government spending to create unproductive jobs can safely be ended -- ranging from military contracts on weapons that never get used, to middling bureaucratic paper-pushing jobs that, when it comes to actually useful labor (i.e. not wasting time in or preparing bullshit presentations and motivational seminars, or posting on webDiplomacy during work hours) have 10 people do what one person could. And then, to take care of the people who are unable to get work, you pay them a guaranteed minimum income.
"But Eden!" you might protest, "If they don't work for their money, why would anyone work at all?" Because no one wants to go through life living on $10K or $15K a year? Duh? Okay, so obviously not *no one*, there will be some people who will choose to do that. Great for them, I guess. The overwhelming majority of society will still want to find work and better themselves financially. For them, those avenues of opportunity are still open. People will still be needed for the foreseeable future in fields that require more dynamic thinking/acting. Computers can process complex economic variables better than humans ever could, but they have no chance of being able to generate the kinds of original insights that lead to optimal decision-making. My laptop, given Excel 2010 and the right numbers and formulas, could spit out USRGDP for 2013 without fail no matter what variables I changed. But it cannot recommend economic policy based on that. It can crunch data on labor costs and prices, but it can't run a business. At the end of the day anything involving dynamic thought or action will probably never be replicated by machines (or at least, that's something for the *far* far future). So there will always be opportunities for people to work and make more money -- and people will want to do it, because no one wants to live on what's effectively the minimum wage if not lower.
"Won't that be expensive to administer?" Nah. $15K for all US citizens of working age (16+) would cost 3.6T per year to administer right now. Sounds like a lot, right? But when you factor in that we can couple this with completely eliminating current welfare spending, all legislative pork and slashing projects that aren't really "necessary," the net cost drops sharply. There would probably need to be an increase in taxes to some extent to cover everything after slashing other spending, still -- total tax revenue in 2012 was $5.1T, for 2013 was $5.5T, projected at $5.9T for 2014, and this policy would take up the majority of that revenue -- but it's not nearly as infeasible as it sounds and is very likely to be solvent in the long run.
"But this isn't very libertarian/conservative/etc. of you!" I disagree with this, I think this is quite the pro-market policy at least. It replaces several inefficient government expenditures with one pristine, streamlined program; and it takes a serious step toward solving both the question of what to do about any supposed societal obligation to take care of its least fortunate members, and what to do about the fact that market economies are entering a state of fundamental change in the wake of technological advancement.