You got that one right. It should be obvious when we see the government owing SS $2.5 Trillion. They use SS taxes for the general fund and spend it all as they get it. If SS is to survive, this has to stop and repay th $2.5 Trillion.
And then what will SS do with the cash? Put it in a lock box and let inflation eat away it's purchasing power?
Or Invest it? And if invest it, then where? Certainly not U.S. government securities, cause that's what we are doing now, and that's one hand borrowing from the other. Maybe Greece government securities? Or Communist China Government securities?
Or perhaps the stock market. SS would depend on the ups and downs of the market and government would own a massive share of corporate stock.
U.S. government securities is the safest place to invest the funds. It does mean that future tax payers are going to have to redeem those securities. But if you put cash away in a lockbox and then drew it out and spent it on SS, you'd be diluting the money supply of the future taxpayers anyway.