I don’t think this Assault Weapons Ban will get through the Washington legislature, which makes me wonder if this is prep for accomplishing the same thing via ballot measure. While Bloomberg very nearly lost the vote in Nevada, and was outright defeated in Maine, he got a stronger margin for his Washington ballot initiative on “gun violence restraining orders” than he did on the private transfer ban. He might be feeling like Washington voters are in the mood for some gun control.
Generally speaking, gun bans have not done very well on the ballot even in liberal states, but as California has shown, things might have changed since the gun control movement last had money for this kind of thing. California is a lost cause, however. I don’t think Washington is. But I also think Bloomberg will keep pushing until he’s rebuked.