Editor’s note: This is the 26th in a series of essays on the history and meaning of the American political tradition.
Between the years 1783 until 1848 the United States realized its greatest territorial expansion. The Treaty of Paris (1783) formally ended the war for independence. It determined that the territory of The United States of America extended westward to the Mississippi River. In 1803, during the presidency of Thomas Jefferson, this boundary was moved westward by the Louisiana Purchase. In 1819, Spain ceded Florida to the United States. In 1846, The Oregon Territory was acquired through negotiation with Great Britain, and in 1848, in the Treaty of Guadalupe-Hidalgo, which concluded the Mexican War, Mexico ceded large territories to the United States, extending the territory of the nation “from sea to shining sea.”
Thus, by mid-century the consolidation of the lower 48 states was nearly complete. To finish the story: in 1853 the United States purchased a strip of land from Mexico that now forms the southernmost parts of Arizona and New Mexico; Alaska was purchased from Russia in 1867, and became a state in 1959; Hawaii was acquired (or seized) and made a territory in 1900, and a state in 1959.
In 1823, the Monroe Doctrine became official US policy. It gave warning to European nations that the United States would regard any more colonization by them in the Western hemisphere as “dangerous to its peace and safety.” This ended the era of European colonization in this hemisphere and the United States emerged as its paramount power. 
The European powers would have to go elsewhere to grow their empires, which they did. Colonialism flourished accompanied by racism, gross injustice, and a growing threat of world war. Nothing really changed.
As the nation grew, it became more and more divided. Two issues divided it: slavery and states rights. The Constitution had established one nation under one supreme law enhanced by a bill of rights, but its benefits accrued mostly to white males, for they alone were enfranchised. Sectional differences persisted — economic, moral and ideological. The right of states to ignore or nullify federal statutes was asserted. There was talk of secession. The future of the union was in doubt.
In a speech delivered to the Senate in 1850, Daniel Webster accurately described the state of the nation: “It is not to be denied that we live in the midst of strong agitations, and are surrounded by very considerable dangers to our institutions and our government. The imprisoned winds are let loose. The East, the North, and the stormy South combine to throw the whole sea into commotion, to toss its billows to the skies, and disclose its profoundest depths.”
Webster desired calm. The question before the Senate was whether to enact legislation establishing the mandatory return of fugitive slaves. Webster, who represented Massachusetts, where slavery was illegal, nevertheless was speaking in favor of what would become the Fugitive Slave Act of 1850. 
With regard to slavery, Webster was a pragmatist. He opposed slavery in principle and expected its eventual abolition, but he accepted the fact that slavery was legal in many southern states; he believed that the Constitution protected it. His stance regarding current laws (at the time) in slave states was that the institutions of slavery in those states must be respected. 
It should be noted that a part of Article 4, section 2 of the Constitution—repealed in 1865 and replaced by the 13th amendment—required that persons in servitude in one state who escape to another state or territory be returned to their masters. It prohibited any state from providing them sanctuary. Webster, among others, interpreted this to apply to fugitive slaves. The Fugitive Slave Act was supposed to implement this constitutional provision.
Webster was convinced of the rightness of his position. He was a public official, a senator, soon to become Secretary of State, and he regarded it as his constitutional duty to uphold the Constitution and the laws of the United States, even those whose essential morality he might find doubtful. Public officials, when carrying out their duties, were supposed to respect the law, and no other principle, which is not to say that Webster was unprincipled. His stance is a perfect instance of stare decisis(see Postscript). This put him in conflict with the Abolitionist Movement and its founder, William Lloyd Garrison (1805–79). 
As a youth, Garrison favored the abolition of slavery. Initially, he supported a policy of gradual emancipation and he joined the American Colonization Society, an organization founded in 1817, to facilitate the return of freed slaves to Africa. This led to the creation of the African state of Liberia. President James Monroe gave his strong support; hence the name of the capital of Liberia, Monrovia. 
By 1830, Garrison concluded that this position was morally wrong, that the only proper course of action was immediate emancipation and enfranchisement of all slaves followed by their integration into American society: freedom and equality. He founded a newspaper, The Liberator, which became the leading voice of Abolitionism in this country. In the first issue he declared his editorial policy: The practice of slavery is a moral wrong of such magnitude that the only way to deal with it is to end it immediately. In his advocacy he promised to be “as harsh as truth, and as uncompromising as justice.”
Webster respected the abolitionists and believed them sincere, but he worried that their practices were extreme and impractical. They were moral absolutists for whom “everything is absolutely right or absolutely wrong,” hence there was no ground for compromise. 
Abolitionists failed to recognize that there were many on the other side, Webster maintained, “religious men, with consciences as tender as any of their brethren in the North, who do not see the unlawfulness of slavery,” and others who “whatsoever they may think of it in its origin, yet take things as they are, and, finding slavery to be an established relation of the society in which they live” fail to see a way end it. He based his argument on the premise that there are good people on both sides of the question.
He feared most of all that a divided nation would be left without a peaceful way to settle its disputes and heal its divisions, that the bond of union would be broken, that secession and war would become inevitable. His worries were prophetic. 
However, Webster failed to mention that the government in which he held office never actively entertained the possibility of ending slavery. He mentions the need for compromise, but never says how that should be spelled out. In the end, this eloquent cheerleader of the nation was paralyzed by his fears, and when facing the devil, he lost his nerve.
Postscript: “Stare decisis” literally means “Stand by what has been decided,”, which in a judicial context signifies a respect for precedent.