There should be no doubt that Henry George was seeking a uniform nationally-enforceable "single tax" when he established the Platform of the Single Tax League of the United States (copied below) on Sept. 3, 1890 in Coopers Union, New York, the first national convention of the Georgist movement. This Congress-enforceable single tax movement contrasts significantly with the state-by-state movement which had existed prior to the national convention of 1890.

However, many Georgists don’t recognize the existence of a uniform national single tax, insisting that George preferred local-government run land taxes. But skimming through the back pages of George’s weekly newspaper, The Standard (1887-1892), reveals that George abandoned the state and local government approach in September 1890, that George was willing to lose well over half his “single tax organizations” if they refused to recognize the final result of the first national convention: the September 1890 Platform of the Single Tax League of the United States.

The Pre-1890 National Platform Era

Before the first national convention in New York, George had begun listing various single tax clubs and organizations, beginning with the October 26, 1889 issue of The Standard, starting out with 105 organizations (operating in 24 states), and ending with the December 31, 1890 issue, which listed 162 organizations (operating in 34 states and 2 foreign countries).

His requirements for being listed in The Standard prior to the national convention of 1890 were very basic: just let him know, as soon as possible, when a group was formed, and if there were any corrections to the group’s name, location, officers, etc.:

“Secretaries of clubs are requested to send any corrections in the list below, and all newly formed organizations are asked to report promptly, either to the Enrollment Committee or The Standard."

The Post-1890 National Platform Era

After the national 1890 Platform was established, things changed dramatically, and George would not allow a group to be listed in the back pages of The Standard unless they agreed to be guided by the 1890 Platform, a copy of which he included with each issue of the newspaper thereafter.

Apparently George’s requirement that his followers align with the 1890 Platform was a lot to ask because enrollment of eligible groups immediately plummeted from 162 operating in 34 states, to only 35 organizations operating in 16 states (according to the January 7, 1891 issue), and then the list gradually grew throughout 1891 until it reached a maximum of 92 organizations operating in 30 states (according to the December 30, 1891 issue).

During this national era, George no longer referred to the listings at the back of The Standard as “Single Tax Organizations,” but as the “Single Tax League of the United States,” followed by: ”A list of organizations that have adopted the declaration of principles made by national conference at New York Sept. 3, 1890,” which was then followed by the request: “Secretaries of clubs are requested to send corrections, notices of the formation of new clubs or of requests for the enrollment of existing clubs to Geo. St. John Leavens, Secretary of the National Committee, at No. 42 University Place, New York.”

Also, at the start of this new national era, George explained the new policy for qualifying new or existing Single Tax groups in the first issue of 1891. The article was entitled “Single Tax League of the United States” and was presented by his National Committee. It stated:

“We publish this week in our STANDARD club list, only such clubs as have endorsed the Platform adopted at the national conference and applied for enrollment in the league. . . . The attention of officers of single tax organizations is called to the resolution adopted at the national conference to the effect that all organizations subscribing to the national single tax Platform shall be eligible for membership in the league. Thus far but very few clubs have formally subscribed to the Platform and enrolled themselves in the league, and officers of organizations that have as yet made no move in the matter are earnestly requested to bring the question before their clubs and apply at once to the secretary of the national committee for enrollment. . . . The national committee is circulating a petition asking the United States house of representatives to appoint a special committee to make inquiry into and report upon the expediency of raising all public revenues by a single tax upon the value of land, irrespective of improvements, to the exclusion of all other taxes, whether in the form of tariffs upon imports, taxes upon internal productions or otherwise. . . . “ The Standard, January 7, 1891, page 17, under Single Tax News

Conclusion

George much preferred a uniform national single tax governed by Congress, instead of governed by numerous state and local governments, who often used very dissimilar single tax methods, and expressed very dissimilar understandings of exactly what was his single tax.

George was clearly seeking to replace his state and local run organizations with a national organization that could be regulated by Congress. However, he died before that was possible. The Supreme Court stuck down his landowner income taxes in Pollock v. Farmers' Loan (1895), and he died in 1897, and his lawyer Thomas Shearman died a few years later in 1900, so neither was around to remind their followers that the national movement became viable again after the 16th Amendment was ratified in 1913.

My general recommendation to the movement is that any organization which today identifies itself as Georgist should at least recognize the 1890 Platform as authoritative, and perhaps even formally swear allegiance to it. Once the Georgist roots of the 16th Amendment are clearly understood, national Georgism will emerge as the best available alternative to economic instability. National Georgism has the answer to almost any economic problem, including the monetary system, tax justness, property rights, economic theory, etc.

Not only does Congress have power to issue ESTIMATED income taxes, but most land monopoly today is caused by owning land in some kind of corporate form in which the shareholders or ownership mix changes quite often, which means there'd be virtually no difference between tax collector opportunities under the income-tax-based LVT vs. under the property-tax-based LVT.