You completely missed my point, so let me be explicit. After the Norman Conquest William essentially used inherritence tax to alter the balance of magnate power in his favour.
In any case, I think you'll find that inherritence tax affects far more that 10% of the population, you can run foul of it with a big house and a classic car. Should you be forced to sell those just because the tax man wants his cut?
Inherritence tax takes no account of liquidity.
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