Economically, if the program exists, the only sensible thing is for it to be mandatory. Otherwise you run into a situation where it's possible for some farmers to get the benefit of the program (higher prices for their crop) without paying for the program (by setting aside some of their crop) and the whole thing collapses.

Also, programs of this nature are old enough that it's really difficult to try to put current interpretations of labels like "socialist" on them; many of the people involved in originally drafting, passing and implementing this stuff would've been, by modern standards, too conservative even for the Tea Party.

(though there is a useful more-recent term to apply here: since the New Deal, farmers and ranchers have essentially been the biggest welfare queens in the United States, to the tune of billions upon billions of dollars in subsidies, tax breaks, favorable land/water rates and government-run price-fixing programs, and generally the anti-"socialism" forces in our government have no problem with requiring welfare recipients to make sacrifices in return for the benefits, so why not be consistent about it?)

I agree, existence must imply the program being mandatory, for exactly the reasons you describe. But perhaps the fact that the justices nearly-unanimously agreed on its unconstitionality means it should not have existed? You have to argue the legality of the program on the merits, not on the basis of "well, if we didn't violate the constitution, the program would not work".

And yeah, I am not trying to pass judgement using the label of socialism, I am trying to draw parallels to what people often decry as one of the evils of socialist states. I understand that these programs were not created in such a context; I certainly do not care about party affiliations or political leanings, only the direct, observable outcomes of the program.

I think it's hard to view in terms of timelessly constitutional or not; the Court's favored interpretations of bits of the Constitution have shifted back and forth widely since the Supreme Court was established.

So I suspect the strongest possible statement is that this is a program most people accepted as constitutional without much controversy at the time of the New Deal, but since then the Court's interpretation (and the political climate in the country, of which the Court is for better or worse a reflection) has shifted.

that would be BS. the new deal was a big push into socialism, programs of the FDR admin. FDR and esp his wife were socialists. Thes type things depressed he economy for years an needed a war to alleviate those problems.