Social Security works because everyone pays a bit of their salary into it – to a point. There’s a salary limit, and above that limit the rest of a person’s salary is exempt. As income inequality widens more money is exempt from social security, which means less money paid into social security. The greater the income inequality, the less secure Social Security becomes. Taken to extremes for illustration, if everyone made the same salary there would be enough for all; if all the income was collected by one person, Social Security would only collect on the first $118,500. That won’t do much to support tens of millions of people. The US Social Security system is somewhere in the middle, and sliding in the wrong direction.
“The Effect Of Rising Inequality On Social Security” – Center For American Progress
Pretending Not To Panic 