>A tax on the fund transactions with citizens of each country would probably be a better way to pay for the SEC and other regulatory and legal services in each country
This is effectively how things already work. Sale of investment products is generally highly regulated in most countries by a domestic regulator and most of those also implement transaction taxes[1].
In effect, the taxation to fund regulation is done at the destination, not the source, which makes sense given that the regulator is typically protecting the investors located in the same jurisdiction.
In the US for example (since this discussion seems to be about the US despite the fact that fund being discussed appears to have nothing to do with the US):
Currently, the US imposes a $0.0042 round-trip transaction tax on security futures transactions and $21.80 per million dollars for securities transactions.[63] The tax, known as Section 31 fee, is used to support the operation costs of the Securities and Exchange Commission (SEC)"
This is effectively how things already work. Sale of investment products is generally highly regulated in most countries by a domestic regulator and most of those also implement transaction taxes[1].
In effect, the taxation to fund regulation is done at the destination, not the source, which makes sense given that the regulator is typically protecting the investors located in the same jurisdiction.
In the US for example (since this discussion seems to be about the US despite the fact that fund being discussed appears to have nothing to do with the US):
Currently, the US imposes a $0.0042 round-trip transaction tax on security futures transactions and $21.80 per million dollars for securities transactions.[63] The tax, known as Section 31 fee, is used to support the operation costs of the Securities and Exchange Commission (SEC)"
[1] https://en.wikipedia.org/wiki/Financial_transaction_tax