The non-defense discretionary (domestic discretionary) portion of the budget includes security spending on areas like homeland security, veterans, nuclear weapons, and foreign operations; safety net programs like housing vouchers and nutrition assistance for women and infants; most of the funding for the enforcement of consumer protection, environmental protection, and financial regulation; and practically all of the federal government’s civilian public investments, such as infrastructure, education, training, and research and development.

The current level of domestic discretionary spending is 4 percent of GDP, about equal to the historical average since the early 1960s. As the graph below shows, Wisconsin Rep. Paul Ryan’s budget implements massive cuts to the domestic discretionary budget, bringing it to 2.1 percent of GDP, the lowest level in over 50 years.