[redahs]

If the thesis of Progress & Poverty is correct, then the cyclic nature of civilization is due primarily to the tendency of the labor cost of acquiring unimproved land for productive workers to increase faster than the rate at which wages can be accumulated to acquire it. If this is the case, then the decline of our present phase of civilization may have begun in the 1930s, when state governments in the United States begun replacing property taxes with sales taxes, as the share of total government revenues raised from property taxes has now fallen from 40-50% to less than 10%, and the share is even lower in other countries.

However while the Roman Republic relied primarily a 1-3% annual property tax on wealth to fund its early expansion from 509BC, it had abandoned public assessed domestic property taxes by 167BC at the latest, yet the the Roman Empire reached its height in 117AD. So the point in time at which a country eliminates domestic property taxes on landed wealth in order to maximize the private capture of rent for its political class is unlikely to represent the peak or maximum of the civilization, but rather an initial inflection point, in which case a peak of our current phase of civilization during the 1960s may have been possible, with the inflection point occurring earlier.

[hevi_jos]

You are mixing things that don't have anything to do with each other. Two empires separated by more than a thousand of years.

While talking about an Empire expansion you omit the biggest factor: You expand or grow conquering-stealing-destroying others and the limit for this is geographic, not taxes.

In the particular case of the Roman Empire they needed to communicate all the provinces, and they did that by sea, mainly using the Mediterranean Sea. There was no train, like there is today(which is a tremendous difference as it is several orders of magnitude of difference transporting things).

Once you conquered all the Mediterranean Sea, there was nothing else to conquer, communicating by land was super expensive. Today it is the size of the world, until we get out to other planets.

Also in today's world there are weapons of mass destruction like nuclear weapons. If you try to grow at the expense of others you could get destroyed.

[sonnyblarney]

"acquiring unimproved land "

When land + labour is the primary means of product, maybe, bu since that hasn't been the case for a while and may not either have been the case in aboriginal territories, I'm not sure it applies.