[pyradius]

Well, many Georgists believe that All Taxes Come out of Rents, so under that belief there is no reason to keep inferior taxes in existence as opposed to collecting the higher rental value that would occur with the removal of those current taxes.

As for levies on externalities, these should be more accurately seen as correcting a market failure, the social cost that society must pay that the consumer/producer do not pay.

Notably, Frank Ramsey and A.C. Pigou can be considered crypto-Georgists -http://blog.lvrg.org.au/2013/09/ramsey-and-pigou-crypto-geor...

"As we shall see, Ramsey not only formulated a rule that leads directly to a “single tax” on land, but also anticipated the so-called Laffer curve in cases where the “single tax” is not employed. Moreover, Ramsey's rule was to be applied after any externalities had been internalized by means of appropriate taxes and bounties."

[TimPC]

Ethically, under Georgism there is a strong moral basis for taxing economic rents and particularly so for taxing land and natural resources. The argument is that we all have equal entitlements to the land and the resources on it. That equal entitlement is forced by taxing adequately for the land value or natural resource value so that it doesn't unfairly benefit the person who holds it at the expense of everyone else.

Georgists are a bit like libertarians when it comes to income taxes. It's very difficult for government to demonstrate a moral basis for interfering in work markets to generate taxation. Libertarians argue that if you are forced to pay 57% income tax you're 57% a slave. I'm not sure Georgists would go that far, but it seems unlikely you'd see implementation of taxes that are both economically less efficient and ethically more dubious than taxation of economic rents.