I think Newsom is trying to convey that California will act as a sovereign state on the international stage, in an economic capacity. He may even be engaging in

I think Newsom is trying to convey that California will act as a sovereign state on the international stage, in an economic capacity. He may even be engaging in diplomatic missions to secure necessary protective equipment. Treaties are not the only way to be an international actor. California's capacity to make credible commitments is severely limited by the constitutional restrictions on states ability to enter contracts with foreign actors, but that may not be enough to stop Newsom from forging informal agreements.