Shortly after Lincoln's inauguration, South Carolina decided to suspend all sales of goods and merchandise to the Union troops who occupied Fort Sumter. This put Lincoln squarely in the same predicament that Buchanan had faced. Union forces were sorely in need of supplies. To send in relief might appear to be an act of aggression, but to withdraw troops would be tantamount to capitulation, and a recognition of Confederate sovereignty.
Under increasing pressure from the federal forces at Sumter, and ignoring the more cautious wishes of his cabinet, Lincoln decided to send supplies to Charleston in the first week of April. When the federal relief expedition arrived at Fort Sumter on April 12, Confederate forces opened fire, and the undermanned and unprepared federal troops were forced to surrender the next day. With this, the war was on.
At the time of this insurrection, the combined forces of the United States equaled a paltry 16,000. Most of these were holding positions on the frontier in an attempt to fight back hostile natives. Now, with a civil war in effect, Lincoln found his forces halved, with the need for numbers raised exponentially. In order to support a weakened federal force, Lincoln made an appeal to the state governors on April 15, with hopes of gaining 75,000 enlisted men. With the period of service set at one hundred days, the forces originally fielded far more volunteers than the government was capable of outfitting. Such are the heady early days of war.
In reinforcing Fort Sumter, and in marshalling federal troops to prepare for battle with the Confederacy, Lincoln had single-handedly made an effective declaration of war. He himself had vehemently opposed such a sweeping step as a member of Congress in 1847, but now he found himself exercising the same executive privileges that James K. Polk had employed during the Mexican War. Inevitably, the criticism against him was considerable.
Two days after the federal mobilization, the Union suffered a key blow when Virginia voted to secede. Mere months before, the Old Dominion had spearheaded a peace conference; now it was lost to the Union cause, shortly to become the heart of the insurgency. Hoping to counteract this defection, Lincoln promptly offered command of the Union armies to Virginian Robert E. Lee, who perforce declined and resigned his military position.
Within the next month, three more states would secede: Arkansas on May 6, Tennessee on May 7, and North Carolina, finding itself regionally isolated, on May 20. Then, on May 23, Virginia voted overwhelmingly to join the Confederacy, placing the rival factions face to face. Shortly thereafter, President Jefferson Davis pushed through a motion to shift the Confederate capital from Montgomery to Richmond, Virginia. As a result, the nerve centers of the Confederate and Union forces lay less than one hundred miles from each other. To be sure, the intervening valleys of Northern Virginia would become a crucial theater of war.
By late spring, the Confederate States of America enjoyed an eleven-state membership stretching from the so-called Indian Territory in the west all the way east to the Atlantic Ocean. As a land mass, it was actually larger than the northern states of the Union. But as a population, it could barely come to halfway, with 9 million against the Union's 18 million.
With the battle lines mostly in place, a few key states remained to be won. Known today as the border states, this group included Delaware, Kentucky, Maryland, and Missouri. As it happened, none of them officially seceded from the Union, although considerable rebel factions wreaked havoc in each case. Since the war often seemed to hang in the balance of border loyalties, Lincoln would make much of his policy with an eye to how it would be received by the loyalists in these states, many of whom continued to be dedicated to the dual preservation of slavery and union.
But in the spring of 1861, it was unclear as to whether the border states would stay in the Union or swing to the Confederacy. Maryland and Kentucky were especially volatile, with differences of opinion paralyzing the executive and legislative branches of state government. Shortly after the conflict at Sumter, rebel sympathizers in Maryland cut telegraph lines and rail ties to Washington, hoping to isolate the Union's command center. By early May, with 10,000 troops defending Washington from a possible attack, Lincoln had declared martial law in Maryland, placing all dissidents under lock and key. Clearly an illegal step in peacetime, this was Lincoln's first significant war measure. While it too drew fierce criticism, it also firmly established him as a strong leader in a time of civil strife.
With tensions also brewing out west, Lincoln sent troops in to restore peace in Missouri. The governor of Missouri protested by calling this action "illegal, unconstitutional, and revolutionary." Against his protests and the protests of many others, Lincoln declared martial law in St. Louis in June, and in all Missouri in August. Although rebels were able to secure southwestern Missouri for the Confederacy, the rest of the state remained loyal, largely because it had been purged of rebel voices. This too was the case in Maryland, and while Delaware and Kentucky were less tumultuous, they also maintained a delicate balance between Union loyalty and rebel suppression.
At the same time that Lincoln was attempting to restore civil order, he also had a set of military objectives to consider. Initially, he had imposed General Winfield Scott's Anaconda Plan, a naval operation that combined a coastal blockade and control of the Mississippi River in hopes of squeezing the Confederacy to death without actually having to fight it. But as sectarian warfare began to break out and weeks turned into months, Lincoln began to lose confidence in what he saw as an overly passive plan.
In the field, the first significant fighting occurred in Western Virginia, where General George McClellan made a push to defend the position of Union loyalists there. A series of early military successes emboldened a group of counties in Western Virginia to refuse the legitimacy of secession on June 11, and this alliance was promptly recognized by Washington as the official government of Virginia. At the nadir of Union fortunes, in an attempt to bolster the Union cause, these counties would be admitted under separate cover as the thirty-fifth state, West Virginia, on June 20, 1863.
But for the moment, such desperate, drawn-out days were far in the offing. With the early successes in Western Virginia underfoot, Union confidence was high, and many believed that the war could be decided in a single major battle. Journalists such as Horace Greeley announced that the Union needed to assert its dominance in a single, swift assault on Richmond. Meanwhile, military tacticians such as Scott were of the opinion that more time should be sent mobilizing.
With the initial Union enlistments about to expire, and the Confederates poised to convene at Richmond, Lincoln caved in to public opinion and ordered a Union operation to cross the Potomac and march on the Confederacy. When General Irvin McDowell, in command of the eastern theater, lobbied Lincoln for additional time to mobilize, Lincoln responded by saying, "you are green, it is true; but they are green also. You are all green alike."
In ordering a hasty, reckless attack of undefined objective, Lincoln revealed that he was equally "green," as were the Washington journalists and politicians who took picnic lunches to the site of the battlefield on the morning of July 21, only to be sent scurrying by the bloodshed they witnessed. Despite enjoying vastly superior numbers, McDowell's early morning attack was routed by forces under the command of Confederate Generals Pierre Beauregard and Stonewall Jackson. The Union catastrophe, known today as First Manassas (also Bull Run), would later be described by poet Walt Whitman as "Lincoln's crucifixion day."