The constitution expressly gives the federal government, congress specifically, exclusive control over immigration law.
It is somewhat encouraging that the court decided we should let elected officials decide this rather than the courts.
However, I think that is only encouraging in the modern world where we have accepted the right of the court to make those decisions.
In the world of the constitution, the court is supposed to be deciding whether the federal government has the right to pass a law that circumvents the will of the people as expressed in their state legislatures.
What is the compelling interest of a person living in Virginia which is harmed if a person in California can grow pot for his own use? Why should Oregon have to convince a majority of people in all 50 states before it gives ITS citizens the right to smoke pot for medical use?
If there IS a compelling federal interest, it doesn't seem to have been argued in this case. The court seems too quick to grant individual's rights that don't exist, and also too quick to deny to the states any rights whatsoever.
The same reason that we want New Hampshire to convince a majority of people in all 50 states before it legalizes homosexual marriage.
It would be more encouraging if the will of the people could decide this (and they have) and not elected officials much less the courts.