License Plates: Public Forum or Government Speech

The Supreme Court heard oral argument today in Walker v. Texas Division, Sons of Confederate Veterans.  Texas permits a wide variety of specialty license plates, emblazoned with various messages (from affinity with a university to endorsement of causes) but refused to allow the Sons of Confederate Veterans to have a plate with the Confederate battle flag on it.  Texas's Solicitor General ran into trouble with his contention that the specialty plates are government speech, immune from First Amendment scrutiny.  (Lyle Denniston's summary of the argument is here.) Let's assume specialty plates are a public forum, perhaps a limited public forum, the limitation being refusal to issue plates bearing a message that can constitutionally be proscribed (e.g., obscenity, fighting words).  That was pretty much what counsel for the SCV argued, even asserting that if a group wanted a plate with a Nazi swastika, or promoted jihad, or illegal drug use, the state could not refuse to issue the plate.  I'm not going to predict the outcome (though I do think specialty plates are a species of public fora) but I am willing to predict a consequence if the Court should adopt the SCV's counsel's assertion:  States will stop issuing specialty plates, especially if obnoxious requests of the sort posited become commonplace.  And I don't think there is any constitutional objection to that action.  Public forums can be terminated.