"Life expectancy at birth in 1930 was  only 58 for men and 62 for women, and the retirement age was 65."

Too many people are just living too long!

Well, that and the addition of Medicare and other increased benefits over the years.  

 
We old people have voted in politicians who want to stay in office.  The young people who are less likely to vote get to pay the extra taxes for those of us who survived.