Why? Because Dems LOVE to spend the American workers' retirement money the minute they get their hands on it, instead of investing it for the workers' retirement like responsible money managers would. They're worse than children with money, and the LAST place retirement funds should be "managed."
Remember, members of Congress and the Senate do not have to pay SS taxes, they exempted themselves and created their own, separate, FUNDED pension plan for themselves, but the "little people" just get their retirement money spent, since government priorities are more important than workers' retirement funds.
SS is an illegal scheme to rob workers' of their retirement funds, that's all.
What helped bankrupt the system was the "welfare" part of it. If people properly and rightfully needed money for disability, widowhood, etc., why wasn't that also the burden of all taxable income, why did the money come solely from a tax on work?