"The congressional session was nearing its end when the President transmitted to the Senate (April 6, 1808) a report on roads and canals, drafted by the Secretary of the Treasury, which comprised the most comprehensive and constructive domestic program that emanated from this administration. If this could have been put into effect it would have constituted a memorable contribution to the physical development of the country, and it could have been expected to contribute greatly to national unity. Circumstances were distinctly unfavorable to its serious consideration at this time, but the report suggests what might have been done if the acceleration of the European war had not created a crisis in foreign relations and if the government had been in a position to initiate a long-range program for internal improvements.
As the term came into general use it referred to improvements in transportation and communication, but Jefferson's own hopes went further. In his second inaugural, anticipating an eventual surplus beyond what was annually set aside to retire the debt, he said that in time of peace this could be applied to "rivers, canals, roads, arts, manufactures, education, and other great objects within each state." He believed that, even in time of war, necessary expenses could be met without burdening future generations with debt and that the return of peace would be a "return to the progress of improvements." A few weeks later, after he had received from Gallatin the pleasing news that receipts were exceeding expectations, he said that this hastened the moment when they could begin on "canals, roads, college, &c." He did not refer to these objectives in his next annual message, and at the opening of the congressional session of 1805-06 his first concern was to secure an appropriation for the purchase of West Florida. Toward the end of that session, however, Congress authorized the beginning of an interstate road across the mountains - from Cumberland, Maryland, to the Ohio River. This enterprise had its genesis in a provision of the Ohio enabling act of four years earlier, following the suggestion of Gallatin, that a portion of the proceeds from the sale of public lands in the new state be applied to such a purpose. But for this financial prospect and this commitment to Ohio a Congress that was representative of local constituencies and responsive to them might have been undisposed to support such an undertaking. Jefferson was soon to become painfully aware of the conflict of local interests that beset it, but he was sufficiently encouraged to devote considerable attention to the subject of internal improvements in his next annual message to Congress. At the time his mind was by no means untroubled. He had recently been apprised of the dangerous doings of Aaron Burr and had issued a proclamation against that mysterious adventurer without as yet charging him with conspiracy by name. But from the Secretary of the Treasury he had learned that before long a surplus was to be expected and he addressed himself to the question of what should be done with it...
...Looking beyond his own term of office, Jefferson suggested that the surplus expected if peace continued should be applied to great purposes of public improvement. In listing these he now placed education first, thereby differing with Gallatin, on grounds of practicality at least. The Secretary of the Treasury believed that provision for roads would be popular and one for a university unpopular. On his advice Jefferson suggested that a national educational establishment might be endowed by a donation of public lands, which in fact would have been relatively painless. Since the objects he recommended were not among those enumerated in the Constitution, the President supposed that a constitutional amendment would be necessary. He stated elsewhere that several years would be required to secure one, and he wanted to get things started now for just that reason. As a rule, Gallatin was more of a loose constructionist, but he believed that even the broadest possible interpretation of the words "general welfare" would not give the federal government the authority to open roads and canals through the several states without their permission. Therefore, he conceded that a constitutional amendment was needed.
"By these operations," said Jefferson, "new channels of communication will be opened between the States; the lines of separation will disappear, their interests will be identified, and their union cemented by new and indissoluble ties." He was lumping the various improvements together, but, judging from what happened, greatest public interest was manifested in roads and canals, just as Gallatin had expected. At the end of the congressional session the Senate adopted by overwhelming vote the resolution which led to Gallatin's report a year later. By-passing the constitutional problem, the resolution directed the Secretary of the Treasury to prepare a plan for the application, to the opening of canals and the building of roads, of which means as were "within the powers of Congress." He was to state what undertakings were required and deserved governmental aid, and also to provide information about works in progress. Thus he was authorized to make a genuinely comprehensive report, and by the same token he needed a long time to prepare it. Meanwhile, he and Jefferson were involved in certain problems and difficulties connected with the Cumberland Road.
Since the cost of the proposed road was soon estimated at $6,000 per mile, exclusive of major bridges, little beyond surveying and planning could be done under the original appropriation of $30,000, which was actually the only one made in Jefferson's administration. According to the terms of the Act on March 29, 1806, he appointed three commissioners to lay out the road, subject to his approval. Meanwhile, he was to get the consent of the states through which it would pass. He had no difficulty with Maryland and Virginia, but when he submitted the first report of the commissioners the legislature of Pennsylvania still had the matter under advisement. The commissioners recommended a route from Cumberland to Brownsville in a direct line to a point below Wheeling on the Ohio River. The act whereby the Pennsylvania legislature gave its consent a few weeks later included a resolution that the route be altered so as to pass through Uniontown and Washington if, in the President's judgement, this could be done consistently with the act of Congress, but that, if not, the road could pass over whatever grounds in the state he should deem most advantageous. On the advice of Gallatin, who believed that because of the conflict of local interest and the opposition of Philadelphia nothing better could be expected, Jefferson agreed to a slight deflection of the road to Uniontown, where Gallatin had formerly lived. This was en route to Brownsville, and the President would not commit himself beyond this later point."
The chapter goes on, specifically addressing Gallatin and Jefferson's views of the Constitutional amendment referred to earlier. I encourage people to read it. It is important to read the Gallatin report in light of the Cumberland Road. Jefferson's concern was with the primacy of the federal government in making these improvements. He did consider the federal government constitutionally empowered to make such improvements, he simply felt that he could not impose upon the states. These were not just state interests, but local interests, were very important at the time. Philadelphia commonly opposed projects that could help western Pennsylvania if the route was directed from Virginia or Marlyand, rather than from Philadelphia. These sorts of provincial disputes stretched back to the French and Indian War in the 1750s, when General Braddock had to squabble with leaders in Pennsylvania, Maryland, and Virginia to determine which route he would cut through the forest to reach the French. Jefferson was unequivocally of one mind with Gallatin on internal improvements, and on the authority to appropriate money for internal improvements. There were lingering Constitutional questions about what he could do without the permission of state governments, but these are hardly libertarian quibbles about public works that modern day libertarians would like to have Jefferson aligned with them on. He wasn't. In the early republic, the nuances of intergovernmental relations weren't entirely ironed out yet - that was the full extent of the constitutional question. Internal improvements are as American as baseball and apple pie, and they are as constitutional as letters of marque and the regulation of the land and naval forces.