People in FL don't want to pay for crap in NY and I'm sure peopl in NY don't want to pay for crap in FL
Such things have been unconstitutional since the founding of the Country, of course. But anyone who wants the Fed gvot to start obeying that particular Constitutional restriction, will have to take a number and stand in a LONG line.
The "Welfare Clause", which many leftists try to pretend means that the govt can do anything it wants that will help any people, actually means exactly the opposite.
When the Const was written, there were two kinds of "Welfare" that legislation generally addressed. "General Welfare" referred to things that help all US citizens equally, such as improving the navigability of major rivers or other such nationwide projects. "Particular Welfare" referred to helping isolated groups (what we now call special interests). Auto workers, or everyone in Connecticut, or black people, etc. And the "Welfare Clause" in the Const, specifically says that the Fed govt can spend tax money on things that will help ALL people in the US EQUALLY... with the specific exclusion of special interests.
Judgements have to be made whether a project's benefits are "general enough", of course. Clearing out the Mississippi River would certainly help all states that adjoin it, and might also help other states whose trade with those states becomes easier; though it might not help a few isolated areas. OTOH, paying to repave a stretch of road in Denver, CO, certainly won't help "all citizens equally".
But I strongly doubt that most of the 9,000 earmarks in the present budget, are "general enough" to pass constitutional muster.
Of course, constitutional adherence hasn't been the strong suit of any administration since the early 1930s. It remains a useful yardstick, though, if only to gauge how much we have to repair, to start running like a real country again instead of a corrupt third-world bazaar.