A Shortage of Presbyterian Ministers
Let me remind the reader: the word "shortage" should not be used without considering its necessary analytical corollary: "at the price offered."
After the Revolutionary War, the Presbyterians began to lose their direct influence in American society, although they retained special influence among the educated elite. In the seven years before the outbreak of the Revolutionary War, the College of New Jersey had sent 75 men into the ministry. Over the next eighteen years, it sent only 39, an average of two men per year. At the same time, the population of the middle and southern states, where Presbyterianism was strongest, rose from 1.75 million in 1783 to 2.75 million in 1790.(30) Two new pastors per year could hardly be expected to keep pace with this population growth, let alone carry the gospel to other regions, especially the Western territories, which were growing even faster. As members moved west or south, older congregations gradually died off.(31) Yet W. W. Sweet began his 1936 collection of Presbyterian Church primary sources with this observation: "No church in America, at the close of the War for Independence, was in a better position for immediate expansion than was the Presbyterian."(32)
What went wrong? From the point of view of Presbyterian tradition, nothing. From the point of view of maintaining the Church's dominant position in the United States, everything. The problem was the Presbyterian tradition of an academically certified ministry. It was restricting the supply of ministers. During the War, there had been a growing demand for Presbyterian ministers. In 1783, the Synod refused to permit the licensing of men who had not received a liberal arts education, which meant the Latin classics. In 1785, the Synod even went so far as to recommend a two-year divinity degree beyond the four-year liberal arts degree. This was postponed for a year and the rejected in 1786.(33) Nevertheless, it indicates what the commitment of the denomination was.
A related problem was that a growing number of graduates of the College of New Jersey ceased to go into the ministry. In the 1770's, nearly half of the college's graduates went into the ministry. It fell to 21 percent during the Revolutionary War and 13 percent in President John Witherspoon's final decade, 1784-94. From 1803 to 1806, it was nine percent.(34) Ashbel Green, who drew up the plan for Princeton Seminary in 1811 and who became the president of the College in 1812, pled before the General Assembly in 1805: "Give us ministers."(35) On the supply side of the economic equation, this shortage was the institutional price of the old Presbyterian tradition of a formally educated, institutionally certified pastorate. This price grew ever-higher over the next century until the Presbyterian seminaries all fell to the humanists and modernists, and Machen was de-frocked. The Northern Presbyterian pastorate was very well educated in 1936; it just wasn't Calvinist.
30. Trinterud, American Tradition, p. 265.
31. Ibid., p. 266.
32. William Warren Sweet, Religion on the American Frontier, 1783-1840, vol. II, The Presbyterians (New York: Cooper Square, [1936] 1964), p. 3.
33. Ibid., pp. 8-9.
34. Mark A. Noll, Princeton and the Republic, 1768-1822 (Princeton, New Jersey: Princeton University Press, 1989), p. 172.
35. Ibid., p. 170.
I'm sure it's true that the [Scots-Irish] Presbyterian churches suffered greatly as a result of the war since they were the heart and soul of the resistance to British tyranny (King George referred to the war as a "Presbyterian rebellion"), although I don't know about the number of churches which may have been burned. 
