It's not because "you had money" simply having money results in 0 taxes. The capital gain comes when you lend your money to some other entity and they use the m

It's not because "you had money" simply having money results in 0 taxes. The capital gain comes when you lend your money to some other entity and they use the money to do work: produce a good, provide a service. Although there is a sect in the US government that wants to tax your money simply because you have it.