Is Wealth Tax realistically feasible?

I just read that CA is considering a wealth tax on billionaires. Not to get into a particular political philosophy, but I'm more curious about the implementation and to settle a dispute with my spouse. I've read a wealth tax has been tried in the past in Europe, but failed miserably. Mainly, because some "wealth" can be moved around to make it difficult to define, such as art. Most homeowners pay a form of wealth tax on their property. But real estate is one of the few things that stays put. If taxation on bank and investing accounts became a nation-wide policy, then many that were subject to it would either leave or convert their accounts into a type of investment that is impossible to assess. I'm guessing mostly into "collectibles" which can only be accurately assessed when sold. What are your thoughts on the real feasibility of a wealth tax?