Here's my own-merits justification: Holding on to wealth is an inherently risky prospect. Let's say you are very wealthy but live in an unstable country. You'

Here's my own-merits justification: Holding on to wealth is an inherently risky prospect. Let's say you are very wealthy but live in an unstable country. You're like a dragon sleeping on its pile of gold. Your wealth is a target. You need to hire considerable amounts of security, stockpile weapons, etc. in order to preserve that wealth. In a stable country, your wealth is not under that risk and you do not need to pay for that risk mitigation. You accrue the benefits of the wealth without taking on the risk. In other words, the act of amassing wealth and keeping it is a direct function of the stability and prosperity of the country in which you live. Because larger amounts of wealth incur larger amounts of risk, it makes sense that a portion of that wealth should be distributed to the country at large: for example, to pay for the less wealthy people who join the military to protect your wealth. Now: what separates that from the existing notion of income tax, capital gains tax, etc? The idea that your wealth, as it is sitting there (not its growth, not what you are earning), is incurring a cost to society, and that society is taking on risk in order to keep your wealth safe. Risk you are not directly paying for. Furthermore, in a stable and modern country holding onto wealth is so safe and protected that you can safely invest your wealth in markets and accrue compound interest. That is the polar opposite of what you would do in an unstable country, where you would keep your wealth hidden away underground, in mattresses, etc. So you are gaining a tremendous wealth-growth benefit by being in a stable country. (This doesn't seem to be addressed in pg's post, which I found confusing, because at 1% taxation you'd be below average market gains and would still gain). I'm not sold on the above argument being a truly compelling and overriding one for wealth tax, it's just some foundational thinking. I do think it explains, in part, why a wealthy person might choose to live in a country with a wealth tax over a country without one, assuming wealth tax became fashionable across most stable countries.