I am saying that the general welfare clause does not give the gov the authority for anything based on the meaning of the words. It does not give authority because that was not the intention of the clause, it merely restates the powers given elsewhere. all the powers that are given are so that the gov can promote the general welfare.
A second gen wel clause elaborates on the power to tax and spend. The state must be able to tax and spend in order to fulfill the duties that it must. Again "gen wel" limits what the gov can do in fulfilling its duties as those things that benefit the nation as a whole.
Madison and the rest (except Hamilton a minor player who was not even authorized to vote a the constitutional convention) all agreed that it would be silly to write a document limiting the powers of gov and then with two words give them the power to do anything at all that could be fit under the large umbrella of general welfare.
Prior to 1936 the supreme court always upheld the interpretation as not giving the gov any specific power.
Since then the courts and congress have gradually added more and more power to congress based on the gen wel clause. At first it may not have been obvious but today the interpretation has become a parody of the constitution.
So to answer your question: the founding fathers, the early courts, and logic tell us that the gen wel clause does not grant powers to congress.
Today illogic, congress, and the recent courts re-interpret the clause in ways that defy common sense. Do they not see that once they have established the broad meaning of the phrase that there is nothing the state cannot do? Why even have a constitution?