We already have extensive experience in the U.S. with a particular type of wealth tax -- called property taxes. I've been paying them in California for 23 years, and they haven't ruined me yet. (The nominal rate on those tends to be about 1%, too.)

Many people with personal wealth of $50m+ start steering significant money into foundations of their own devising. There's a good debate to be had about whether society is better off with the richest people creating their own philanthropy and social-reform strategies, or having them hand over the $$ to the government for its version.

I'd rather see individual strategies proliferate, on the belief that the government doesn't always know best. But the idea that a 1% tax will bring ruin on successful entrepreneurs grossly underestimates the way that fortunes keep growing.