Of most importance in later days was Mon roe's stand on the difficult diplomatic problem of his time, arising out of the independence of the South American states, and of the effort of European rulers, combined in the Holy Alliance, to repress popular uprisings. We acknowledged the independence of the South American states; and as long as the European powers confined their policy to the eastern hemisphere, their principles were none of our affair. There came, however, evidences of an intention to overcome the new states on this side of the ocean, and Monroe issued his famous message of 1823, an nouncing that we had no purpose to interfere with European affairs, but that on the other hand any attempt on the part of the European powers to extend their system to any portion of this hemisphere would be considered °as dan gerous to our peace and safety.° In this °era of good feeling?' characterized by nationalism as it was in the main, arose a great controversy between the free and slave States, a controversy which, as Jefferson said, °rang out like a fire bell in the it fore told sectional animosity and strife. When the Constitution was adopted, slavery existed in nearly all the States, but was gradually disap pearing in the North, and even in such a State as Virginia there was strong opposition on prin ciple to the whole system. By 1820 slavery was practically extinct north of Maryland; but in the meantime, because of the invention of the cotton-gin and the development of textile ma chinery, slave labor had become profitable at the South and the black population had much in creased. Virginia statesmen no longer cried out against the system, which was now firmly fast ened not only on the Southern States of the old 13, but also west of the Appalachians in the rich and fertile country from the Ohio to the Gulf. The climate and soil of the Southern States were favorable to the African and to the industries based on slave labor ; and the big cot ton plantation became the significant feature of Southern life. At the beginning of the govern ment almost no cotton was grown in America or exported from its harbors; in 1824 142,400,000 pounds were sent abroad. And thus the South ern States were grounded on a system of labor at variance with the labor system of the free North, which, in turn, had been extending over the mountain range and on to the Missis sippi, filling the western land with laborers who worked with their own hands for gain. Two different industrial systems faced each other across the waters of the Ohio.
The Territory of Missouri lay in the path way of the expanding West. Slavery already existed there, but when the people asked admis sion to the Union. difficulties arose. The South wished to have Missouri admitted as a slave State; the North, not averse to its admission, desired to see it a free State. The South needed to have room for territorial expansion, since its agricultural system was ever demand ing virgin soil and fresh acres. The North was unwilling to see a new slave State added to the Union and many — it is difficult to say how large the number—were opposed, on principle, to the extension of slavery. The sections were now equally represented in the Senate, though the North had outstripped the South in popula tion. In the House of Representatives the mem bers from the free States numbered 133, while from the South, in spite of the fact that three fifths of the slaves were counted as a basis of representation, there were only 90 members. If the South was to maintain itself politically, it needed to retain or strengthen its hold on the Senate. The contest over the admission of Mis souri was long and bitter. Before it was con cluded, Maine, hitherto a part of Massachu setts, sought admission, and the application at once complicated and lightened the problem. The effort to admit Missouri with a restriction providing for the gradual disappearance of slavery within its limits was not successful; and finally it was admitted as a slave State; the act providing for its admission stipulated that, ex cepting within the limits of the new State, slavery should not exist north of the parallel of 36° 30', °in all that territory ceded by France to the United States under the name of Louis iana.° This was the famous Missouri Com
promise (q.v.). Maine was admitted, and the Senate was still evenly divided between the sections. Even more plainly than before, the Union was composed of two series of States, differing one from the other in industrial prac tices, in social as well as economic habits that were likely to beget misunderstandings and to develop antagonisms. There was really a division of the national domain between the two systems.
The admission of Missouri as a State, only 18 years after the vast region between the Mis sissippi and the mountains was purchased from Napoleon, is a proof of the remarkable growth of the United States. When the Constitution was adopted, only a few thousand people had found their way over the Appalachians; by 1810 there were dyer 1,000,000 inhabitants in the Mississippi Basin. Kentucky, Tennessee and Ohio had been admitted as States. At the out break of the War of 1812, Louisiana came into the Union, and after the war was over, in the period of industrial reorganization that ensued, thousands flocked into the Western region, peopling the wilderness, clearing the forest for farms and plantations, building villages, estab lishing civil government. In 1816 alone 42,000 K settlers entered Indiana. In six years en tucky more than doubled her population and Ohio was not far behind. Almost as if by magic prosperous towns appeared where but a short time before there had been nothing but forest or empty prairie land. Before the Mis souri Compromise, Mississippi, Alabama, In diana and Illinois had joined the Union as States. And yet this rapid peopling of the new country was but an example, extreme, perhaps, but typical nevertheless, of the movement that was characteristically American and resulted in the occupation of the great West, as far the Pacific, in less than 100 years from the forma tion of the Federal government.
With this Western movement came certain political acts and tendencies, not all attributable solely to Western influence, and yet intelligible only as we see the growth of the country and the development of national sentiment. Already steps had been taken for the building of a great national highway into the West. This at first the South had not opposed; even in 1816 Cal houn, moved by the national spirit of the time, in advocating the expenditure of money for in ternal improvements, exclaimed in the House: °Let it not . . . be forgotten — nay, let it forever be kept in mind — that our vastness exposes us at the same time to the worst of calamities, dissension. We are great and rapidly, I was about to say fearfully, growing. . . . Good roads and canals will do much to unite us.° Ere long the South opposed the building of roads at national expense; but the West naturally favored making means of access to the East. Henry Clay was the strong advocate of internal improvements; and from him, too, a Western man with Western interests, came the demand for a protective tariff and the "Ameri can system." New England at first objected to the tariff as a check to its commerce, while the South was not averse • to the practice. But in 1824 the Northeastern States approved protec tion and the South opposed. Each section, North, South and West, was coming to an ap preciation of what seemed its economic in terest. The Cotton States, given up to agricul ture and to the raising of a great staple, much of which was exported, naturally objected to a tariff which seemed to be a burden on their in dustry for the benefit of the manufacturing and commercial North. In 1828 the so-called "tariff of abominations" was passed, a measure which in many ways merited its name. This aroused strong Southern opposition and ushered in a course of argument and protest against the action and assumption of the national govern ment, which, with some variation, continued as occasion demanded till the outbreak of the Civil War.