This is a very odd development. It is almost as if the coastal elites are banding together against the rest of the country, and are semi-officially declaring themselves independent nations.
You mean like “states?”
Very curious.
It actually makes a lot of sense, especially in areas where you have metro areas that cross state lines. You don't want one state to re-open businesses while the neighboring state keeps them shut down. You'll have a large-scale movement of people across state lines that will ultimately make the problem worse.
New York City alone has a commuter region that includes parts of four states -- NY, NJ, CT and PA.
In a way they have already doing this for years. One state will pass a law, then other states jump on board with same law, often the same language since it was written by some left-wing NGO. More recently they did Medicaid expansion, state by state and climate change legislation after Trump pulled out of the Paris agreement. It's completely legitimate and the 10A gives them the power to do so. But I think what we see forming here is a recognition that the ad hoc legislation of the past was a stepping stone to more coordinated efforts between governors. It works perfectly for them. Setup a shadow government and call it a central committee, Soviet style. While the USSR had leaders, they were often puppets of the central committee and the party. There's no reason for leftist governors to have a leader, everything is decision by committee anyway. No leftist has the testicular fortitude to make decisions and lead on his own. Hence the unified reopening of states.