Social Security and Medicare expense issues have been the topic of various pending doom scenarios with competing projections that the system will be

Social Security and Medicare expense issues have been the topic of various pending doom scenarios with competing projections that the system will be bankrupt in 20 years to scenarios that it will remain in surplus or balanced. What factors are contributing to the concern about the future viability of the system and what are some of the policy actions that have been or could be taken to secure its future?