Here is Hamilton ont the question of taxes and general welfare clause
It kills most con bullshit on the issue
A question has been made concerning the constitutional right of the Government of the United States to apply this species of encouragement; but there is certainty no good foundation for such a question. The National Legislature has express authority "to lay and collect taxes, duties, imposts, and excises, to pay the debts, and provide for the common defense and general welfare," with no other qualifications than that "all duties, imposts and excises, shall be uniform throughout the United States; and that no capitation or other direct tax shall be laid, unless in proportion to numbers, ascertained by a census or enumeration, taken on the principles prescribed in the constitution," and that "no tax or duty shall be laid on articles exported from any State."
These three qualifications excepted, the power to raise money is plenary and indefinite, and the objects to which it may be appropriated, are no less comprehensive thin the payment of the public debts, and the providing for the common defense and general welfare. The terms "general welfare" were doubtless intended to signify more than was expressed or imported in those which preceded; otherwise, numerous exigencies incident to the affairs of a nation would have been left without a provision. The phrase is as comprehensive as any that could have been used; because it was not fit that the constitutional authority of the Union to appropriate its revenues should have been restricted within narrower limits than the "general welfare;" and because this necessarily embraces a vast variety of particulars, which are susceptible neither of specification nor of definition.
It is, therefore, of necessity, left to the discretion of the National Legislature to pronounce upon the objects which concern the general welfare, and for which, under that description, an appropriation of money is requisite and proper. And there seems to be no room for a doubt, that whatever concerns the general interests of learning, of agriculture, of manufactures, and of commerce, are within the sphere of the national councils, as far as regards an application of money