According to a January 2017 report from the Congressional Budget Office (CBO), spending on entitlement programs for the elderly is the primary factor driving increased budget deficets over the next 10 years. The CBO states:
Outlays rise faster than revenues—by about 5 percent a year, on average—increasing from 20.7 percent of GDP in 2017 to 23.4 percent in 2027, approximately 3 percentage points above their 50-year average. Relative to the size of the economy, the increase in mandatory spending—specifically, for Social Security and Medicare—and payments for interest on the government’s debt would more than offset a significant projected decline in discretionary outlays, which are already more than 2 percentage points below their 50-year average
This projection shouldn’t be news to those following fiscal policy in recent years, but if President Trump wants to increase spending and lower taxes without addressing the issues of Medicare and Social Security, one can expect the U.S. debt burden to grow even beyond the CBO’s projections.