Lee's next stroke was even bolder. Crossing the Potomac River in early September 1862, he invaded western Maryland, where the forthcoming harvest could provide him with desperately needed supplies. By seizing western Maryland, moreover, Lee could threaten Washington, indirectly relieve pressure on Richmond, improve the prospect of peace candidates in the North's upcoming fall elections, and possibly induce Britain and France to recognize the Confederacy as an independent nation. But McClellan met Lee at the Battle of Antietam (or Sharpsburg) on September 17.

The cost of war in blood and money was changing the way ordinary people in the North felt about slavery.  Anger at southerners more than sympathy for slaves caused this change…Gradually Lincoln came to the conclusion that the United States should try to free all slaves.  He would have preferred to have the states buy the slaves from their owners and then emancipate or free them.  This idea was known as compensated emancipation.

The South's demand for an effective fugitive slave law was a major source of sectional tension. Efforts to enforce the law resulted in abuses that repelled many northern moderates. In one instance, a free man named James Hamlet was seized in New York and sent into slavery. Riots directed against the law broke out in many cities. In Christiana, Pennsylvania, in 1851, a gun battle broke out between abolitionists and slave catchers, and in Wisconsin, an abolitionist editor named Sherman M. Booth freed Joshua Glover, a fugitive slave, from a local jail.

Many Americans in 1850 took this prodigious growth for granted. They considered it evidence of God’s beneficence to this virtuous republic, this haven for the oppressed seeking refuge from Old World tyranny, this land where all (white) men stood equal before the law. During the 1840s a group of expansionists affiliated with the Democratic Party began to call themselves the “Young America” movement. They proclaimed that it was the “Manifest Destiny” of the United States to grow from sea to sea, from the Arctic Circle to the tropics.

Attempts to enforce the new law provoked wholesale opposition. In Congress, a Free Soiler declared that it would be the same as 'murder' to return a fugitive to slavery. Eight northern states attempted to invalidate the law by enacting 'personal liberty' laws that forbade state officials from assisting in the return of runaways and extended the right of jury trial to fugitives. Southerners regarded these attempts to obstruct the return of runaways as a violation of the constitution and federal law.

Some Southerners had threatened secession at the prospect of Lincoln's election. Now the moment of decision had arrived. On December 20, 1860, a South Carolina convention voted unanimously for secession; in short order Alabama, Mississippi, Florida, Georgia, Louisiana, and Texas followed. On February 4, delegates from these seven states met in Montgomery, Alabama, and established the Confederate States of America.

A superb administrator and organizer, McClellan was brought to Washington as a commander of the nearly named Army of the Potomac.  In the months following his appointment, McClellan energetically whipped his army of dispirited veterans and fresh recruits into shaped.  The troops cheered their boyish general when he rode among them, in part no doubt because of his reluctance to send them into battle.  Lincoln said McClellan had a bad case of “the slows,” and indeed McClellan, for all his energy, lacked decisiveness.  Lincoln wanted a general who could advance, take risk

Coercive measures against disloyalty were perhaps as much a boost as a hindrance to Democrats, who took up the cause of civil liberty. Early in the war Lincoln assumed the power to suspend the writ of habeas corpus, which entitles people in jail to a speedy hearing. Lincoln also subjected "disloyal" persons to martial law - often on vague suspicion.

[Lincoln] finally hit upon a solution that evidenced that mastery would mark his presidency. He decided to send in unarmed ships with supplies but to hold troops and warships outside the harbor with authorization to go into action only if the Confederates used force to stop the supply ships. And he would notify South Carolina officials in advance of his intention. This was a stroke of genius. It shifted the decision for war or peace to Jefferson Davis.

[Lincoln] stayed in Springfield until mid-February 1861, biding his time. He then boarded a train for a long, roundabout trip, and began to drop some hints to audiences along the way. To the New Jersey Legislature, which responded with prolonged cheering, he said: "The man does not live who is more devoted to peace than I am...But it may be necessary to put the foot down." At the end of the journey, reluctantly yielding to rumors of plots against his life, he passed unnoticed on a night train through Baltimore and slipped into Washington before daybreak on February 23.