Right now only a tiny portion of our nation holds the majority of wealth, and really how much work do they do for it?

This is my point, basically. The only way you're going to change that is through violent revolution, given the state of the American political process (they own it, more or less, and voter apathy has never been higher, while turnouts never lower). However, nobody (including me) wants violent revolution, as sociopaths usually rise to the top in a power vacuum situation and who wants to see people die?

basically, people have enough creature comforts, even at near-poverty levels, that they're way too complacent to fight to change things.

It may be possible in the future, like you said, but I still don't see how it will be fiscally possible. You said:

I would challenge your assertion that we'd be asking a tiny portion of earners to fund the rest of the nation or that people would lose their motivation to work.

But you did not explain how you would challenge that assertion. No matter how you slice it, a basic income that actually pays the rent and puts food on the table can only be given to everyone in the US if we spend our entire GDP on it, and that GDP's going to go way down if we're suddenly not collecting income taxes from a ton more people who are on the dole. Double-blow: we're not collecting those taxes and we are giving away money. All that money has to be accounted for, and it can only come from those who have a ton of money--the top 10% or so. And that top 10% A)isn't willing to give it up B) Shouldn't have to.

Now, I agree that income inequality is insane in this country and we need a more progressive tax code, but for basic income to work, it'd be less "progressive tax code" and more "bankrupt anybody with more than a million dollars."

Not gonna work. Maybe some future idea/program/paradigm shift will solve these sorts of problems, but BI, at least in the US, isn't viable and likely never will be for mathematical, political and practical reasons.