So long as the ratio of payers to dependents was about equal (and so long as earnings at least kept up with inflation); there was no apparent problem with these pay-as-you-go social programs. Unfortunately, the fuse on the demographic bomb has already been lit. There will soon be many more dependents than payers. At that point, expect the payers to rebel, and the system to collapse.
Meanwhile; you can take some comfort in the fact that these unfunded liabilities aren't accruing compound interest. If they were, the U.S. would have been bankrupt a couple of decades ago.
Thanks for the clarification ... you’re right. I keep forgeting that the statement I get from SS each quarter doesn’t represent money in an existing account for me ... its money they expect someone else will have to pay when I retire.