"U.S. Constitution, since Article I, Section 8 specifies that the Congress provide for national defence and general welfare." I'm pretty sure "general welfare" (stated above) is not related to "programs such as Social Security, Welfare, Medicare, Medicaid, and unemployment compensation". Wow. What a stretch!

The Constitutional Dictionary
Welfare
welfare n. 1. health, happiness, or prosperity; well-being. [<ME wel faren, to fare well] Source: AHD

Welfare in today's context also means organized efforts on the part of public or private organizations to benefit the poor, or simply public assistance. This is not the meaning of the word as used in the Constitution.