The "general welfare" clause appears twice in our Constitution, in the preamble and in Article 1 Section 8.
"The Congress shall have Power to lay and collect taxes, duties, imposts, and excises, to pay the debts and provide for the common defense and general welfare of the United State."
The Cato Journal states in a book review about Leonard R. Sorenson's book Madison on the "General Welfare" of America: His Consistent Constitutional Vision, that the general welfare clause "has been a source of great mischief. Interpreted elastically by constitutionalists of the "living document" persuasion, the clause has helped serve up a gourmand's feast of government programs, regulations, and intrusions that would have been unimaginable to the Framers."
Between 1781 and 1913, the federal government consisted of eight cabinet level departments which presently employ 489,852 employees. Since 1953, roughly coinciding with the beginning of the "Great Society" seven departments have been added, Health and Human Services (HHS, originally named Health, Education and Welfare) Housing and Human Development (HUD), Transportation, Energy, Education, VA, and Homeland Security, with total employment of 692,803. During the last 59 years the federal government has more than doubled its size during its first 172 years. (DOD is excluded from calculations.)
HHS doesn't heal, HUD doesn't develop, Transportation doesn't transport, Education doesn't educate, and Energy doesn't energize.
What these departments try to do is promote the "general welfare." Generally they receive hunks of tax monies, and spend it according to the bureaucracy's "vision" and produce mandates, rules, and regulations for the rest of us.
Alexander Hamilton may have been the only founder familiar with the Wealth of Nations, published in March 1776. The term capitalism, economics, public good vs. private good, were not yet in use. For all practical purposes the United States invented capitalism, what Adam Smith referred to in his book as "system of perfect liberty" or "system of natural liberty."
If Mr. A thinks something is good for society (the public) that doesn't make it a public good, (i.e. a proper concern for Congress under the general welfare clause) so that Mr. B, Mr. C, and Mr. D have to pay for it.
It would be great for society if all cars on the road had a tune-up every year. But I don't expect anybody to pay for my car's tune-up.
Economically speaking, maybe good for the public, but certainly not a public good.