Yes, I do get that. But it has nothing to do with Social Security, and everything to do with our monetary system.
I have read and thought much about that very problem, what to do about it and how to fix our monetary system. The basic problem, as I see it, is that in theory a centralized fiat currency system, combined with fractional reserve banking, can be the most efficient one provided that it's properly managed and run. However, as we both know humans are very bad at running these systems and there are many chances for corruption, politics and fraud to reduce the efficiency of the system and inject unfairness. Indeed, power over the money seems to lead even the most virtuous men astray; it's extremely corrupting. The next best alternatives are commodity based monies, gold and silver for example, but these tend to be less efficient and there's no longer sufficient commodity in the form of either gold or silver bullion to provide any significant transactional backing compared to the size and scale of our global economy. It's a tough problem to be sure and many men and women, much smarter than I, have thus far been unable to square the circle on this one. Like all theoretically perfect systems, we humans tend to fall short of noble ideals in practice.
The only way for the debt to go is up.
It doesn't have to be that way. At any given time there's a limited amount of credit in the form of free capital available for investment in the real economy, so any debt beyond that simply adds to inflation and waste. For example, look at all of the foreclosed and half-finished homes around the United States these days. They're proof positive that debt and credit in dollar terms can easily outrun the underlying capital available to complete all of those projects (hence the boarded up and half finished homes). I tend to view this problem as a design flaw in our monetary system.
No more debt, no more money.
Yes, I'm well aware of that "feature" in our present monetary system.
That's a separate issue from whether we can afford to take care of our elderly.
I would say that they're related, because poor monetary policies on the part of central banks combined with spending problems in governments, made possible by the abuse of those monetary systems, have real negative effects in the real economy. They make taking care of our elderly harder than it otherwise would be. So the problems are interrelated as I see it. We young workers are already hard pressed to raise families and take care of aging parents. Payroll taxes are already as high as they realistically can be, to ask for more would be counter productive. Social Security is being broken by demographics. It's a demographics problem so how can tweaking a few parameters in the present program solve that while still meeting people's expectations for the program? Of course, it doesn't help that the government has been coy and promoted false perceptions and lies surrounding the program; inflating people's expectations for a program that was originally designed only as bulwark against absolute poverty and starvation in old age, not as a pension or retirement system.