No. A "one time" tax would become an annual tax, and the result would be the very rich fleeing the country or restructuring their assets to avoid the tax. The result would be breaking up small businesses between $10M and $50M, big enough to have to pay the tax but too small to survive or dodge the tax. The result would be more productive people going Galt, and leaving no one behind who knows how to create jobs.
You are right - he is just talking the talk and it means nothing in the long run. How many times has he declared bankruptcy? And he wants to run the country???