"at least those people working in the sweatshops aren't homeless"
Bizarrely enough there are many people who have jobs, yet cannot afford housing. Something about rising real estate prices.
A union makes sense when the workers have specialized interests, but for unskilled labor isn't it simpler just to work through the overarching government?
Personally I would expect large corporations and the very rich to be capable of defending their position against any reasonably predictable shift in the economic environment, since they have resources and motivation to lay out more comprehensive contingency plans than anyone else. That extra productivity from "Job 2" doesn't just vanish into the aether. Higher minimum wage means the poorest people have more money, then they turn around and spend that money at Walmart.
The ones who lose out from a higher minimum wage would be the middle managers, who are then less free to treat bottom-tier workers as interchangeable, disposable, safe targets for petty abuse. With higher wages, those workers will have more of the financial security that makes them willing to risk standing up for themselves, and specialized skills that make them more expensive to replace. That's what wage compression, reductions in turnover, and improvements in organizational efficiency look like from the trenches.
This is an adequately accurate summary, though you may have missed the pun.
"Let's help everyone equally, or in proportion to their needs or something" is easier to agree on than "let's devote the entire GDP of Russia to my personal enjoyment, and maybe my friends and allies in proportion to their loyalty." With the former, people quibble over definitions and in-groups and details of implementation; the latter, even Putin dares not propose openly.
I'm not claiming that propensity to charity or altruism causes, or even particularly correlates with, economic development. I'm just saying that economic development is good, and that it's marginally better for the world economy when some excess food goes to a human who'll eat it, rather than sitting in some warehouse until it rots, even (perhaps especially) if the human in question can't afford to buy food at the going market rate. When rational people see something being squandered, they prefer to throw that resource into charity, where it will do some good, rather than preserve the wasteful status quo.
Or you are so unfocused you solve none of them?
You start with the especially vast, horrific problems which can be sorted out cheaply, like scurvy and polio and malaria, then proceed to more complicated, less severe stuff as returns begin to diminish. That's the whole idea of evaluating medical interventions in terms of dollars-per-QALY, isn't it?
Some combination of Social Security Disability payments, caring friends and family, private-sector charities, and hospital emergency rooms that aren't allowed to check for ability to pay before providing treatment. It's a bad system with a lot of cracks to fall through, and a distressing number of poor people suffer miserable pointless deaths.
Colonizing the galaxy is a political problem, not a question of engineering possibility. A sufficiently zealous world government could jump-start asteroid mining with an Orion Heavy Lifter, construct mirror arrays near the sun, and start lobbing around interstellar VNMs, all with relatively simple refinement and application of existing technologies. Problem is, the best way of putting a complete industrial base into orbit runs afoul of certain atmospheric nuclear test ban treaties.
Without a reactionless drive there's no point sending a colony ship faster than about 60% of the speed of light. Gotta save some remass to decelerate.
It's an investment.
When you have some asset that you don't immediately need, and somebody else would be able to make better use of it, renting it out or giving it away enriches the whole system. Then you get to live in that richer system and enjoy the benefits. Your quality of life is better when you live somewhere with reliable electricity, uncensored internet, and trivial access to potable water, right? A fancy car isn't much fun without fuel or decent roads.
Helping somebody on an altruistic basis is just another transfer of resources toward where they'll be used more efficiently. It's less directly profitable to the donor than sale or rent, but reduced transaction costs and targeting explicitly based on need means the net societal benefit can be greater.
Maximizing overall QALYs may be, in itself, a less efficient way to improve the society you live in than slanting toward helping your immediate social circle, municipality, or nation, but it's easier for everyone to agree on, and every dollar or man-hour spent on arguments is one less to spend on getting the actual work done. Besides, we live in a world where more of the mercury contaminating fish in Lake Michigan comes from industry in China than from local sources. You never know whose problems might land in your back yard, so just go ahead and solve all of them.
All that social stuff, instinctive empathy and cultural expectations alike, is secondary. It developed so people can do the right thing without needing to understand why it's the right thing.
Pretend to be a radical environmentalist or something.
We're all empiricists here, so let's run an experiment. You've got this theory that gjm won't understand if you try to explain. How 'bout you stop rehashing that, actually try to explain some of those technical terms you mentioned earlier, and see how your theory holds up?