Right, it doesn't seem too difficult or unreasonable to treat the value of something used as collateral for a loan as an opportunity to establish its realized v

Right, it doesn't seem too difficult or unreasonable to treat the value of something used as collateral for a loan as an opportunity to establish its realized value from a capital gains perspective. This could also help resolve the issue with taxing non-liquid asset values (like homes), in that you hit wealth when it is utilized (easy to judge) rather than when it is generated (often difficult to judge).