For 250 years, the US Army has adapted as a living organization composed of operating units and institutional organizations that generate combat power. Institutional strategy, the mechanism by which senior Army leaders guide the department over the long term, establishes policy and prioritization for resourcing and gives coherence to the Department of the Army’s purpose—to provide trained and ready forces for employment.

However, during the eras where wars end and the winds blow an optimistic future filled with peacetime planning considerations the Army has had to deal with the realities of reduced budgets and manning levels. All while maintaining ever-increasing responsibilities or control over distant territories as well as a growing expectation to handle new and challenging assignments that it has never encountered before. This was never truer than in the post Mexican American War (1846-1848) era where the volunteers were discharged from Federal service and the authorized numbers of U.S. Soldiers were decreased to meet the demands of the budget. At the height of the war against Mexico the U.S. Army grew to an approximate 73,000 Soldiers with 35,000 of them being considered as a part of the Regular Army. After the war ended the United States grew through the Treaty of Guadalupe Hidalgo with an approximately 525,000 acres of land being ceded. Land that was already beginning to be settled and would explode in size after the California gold rush (1848-1855) now needed to be garrisoned by the Army. The, now peacetime, Army would be spread across more than 100 posts, forts, and cantonments across the new frontier. As the years progressed between 1848 and 1860, the Army would shrink through reduced authorizations to 10,320 (set by the 1815 authorized strength of 10,000). However, as the immense task of exploring, securing and settling the west became apparent, the Army would gradually grow to 16,367 (newly approved authorized strength of 18,000) by December 1860. Of those 16,367 less than 4,000 were stationed east of the Mississippi River.

The Army kept itself busy improving the Nation during the interwar years as well. For generations, the Army was to be the only force for law and order throughout thousands of square miles. As the Army explored this vast new conquest, the Corps of Topographical Engineers played the leading role. Lieutenant and later Captain George G. Meade would supervise lighthouse construction and inspection in New Jersey including those at Long Beach Island, Atlantic City, and Cape May, and in Florida at Jupiter, and in the Florida Keys. Meade would then go on to survey the Great Lakes. In Washington, D.C., Army engineers-built aqueducts, bridges, and public buildings. In 1853, Lt. Montgomery C. Meigs, future Quartermaster General for the Union Army during the Civil War, received the mission of constructing a permanent water supply for the city. The project included an aqueduct with two bridges that later carried traffic as well as water pipes across the Cabin John and Rock creeks. In the years leading up to the Civil War Meigs also supervised additions to the Capitol which included the House and Senate Wings and the dome. Lieutenant Robert E. Lee would also conduct a survey of the Mississippi River for future flood control projects. These improvements were being spearheaded all over the country as resources allowed.

Technological advances and modernization efforts.

As the Army’s authorizations slowly increased, the new (1853) Secretary of War Jefferson Davis and the future President of the Confederacy looked to reinvent how it operated. He encouraged the Army’s total authorization level be set at 27,818 (which ultimately failed), he encouraged a reorganization to expand mounted forces to handle the issues in the vast west which added two new regiments of cavalry and infantry each, as well as embracing new technological advancements. At Secretary Davis’s insistence, the new infantry units were armed with percussion-cap, single shot, muzzleloading rifled muskets instead of smoothbore flintlock muskets the Army had been using since the Revolutionary War in different versions. The invention of the Minnie-ball bullet made it now possible to have dependable muzzleloading rifles fire as fast as the smoothbore muskets. The combination of these advancements increased accuracy from an approximate 100 yards with the smoothbore flintlock, to 400 to 600 yards with the new rifle. A similar innovation also was applied to artillery giving increased range and accuracy.
As national armories and arsenals began producing the new advanced equipment, development in tactical doctrine lagged. Due to the new advancements and greater ranges in weapons, an emphasis was placed on the skirmisher formation or open order tactics preceding the main line of closed formation of infantry which remained in rigid adherence. This adherence was reinforced in all of the military academies across the Army particularly within West Point. Henry Wager Halleck, a West Point Graduate (Class of 1839), made a name for himself before the war by publishing a thorough study on what many historians have termed “professionalism.” In 1846, he published Elements of Military Art and Science, which became the standard textbook on strategy for cadets at West Point. In this work, Halleck argued that American soldiers needed to receive specified training and studies just as other vocations received codified instruction. “If years are requisite to make a good sailor, surely an equal length of time is necessary to perfect the soldier; and no less skill, practice and professional study are required for the proper direction of armies.” Halleck also advocated for methodical field tactics over brash decision making, thus supporting the view that good military leadership was a trained skill rather than some innate attribute that one might possess without any professional training. He would later serve as President Abraham Lincoln’s Chief of Staff responsible for management of the Union Army during the Civil War.

Outbreak of War

Increasing tension was soon becoming apparent, and between 1857-1861 tensions over slavery ran into the western territories and its potential future expansion. Abraham Lincoln’s election to the Presidency on November 6, 1860, triggered the long-simmering political crisis. Lincoln’s party was opposed to the expansion of slavery into the new western territories. This threatened both the economic and political interests of the South, since the Southern states depended on slavery to maintain their way of life and their power in Congress. South Carolina, on December 20, enacted an ordinance declaring that “the union now subsisting between South Carolina and other States, under the name of the ‘United States of America,’ is hereby dissolved.” Within six weeks, six other deep-South states seceded from the Union and seized Federal property inside their borders, including military installations, save Fort Pickens outside Pensacola and Fort Sumter in Charleston Harbor. To the seven states that formed the Confederate States of America on February 18, 1861, at Montgomery, Alabama, the U.S. government’s retention of the forts was equivalent to a warlike act. To provide his fledgling government with a military force, on March 6 the new Confederate Executive, Jefferson Davis, called for a 100,000-man volunteer force to serve for twelve months. The now Union Army was suddenly thrust into crisis as 286 of the 1,080 officers in uniform at the start of the war would resign or be dismissed to return to their Southern state. In its current position the Army was unable to respond as a unified force to for the mission of forcibly returning the Southern states to the Union. After his inauguration President Lincoln would call for 75,000 volunteers for three months of federal service to secure the capital and other key locations. These militiamen came from virtually all northern states as newly organized state common (compulsory) militia units, volunteer militia companies, and individual volunteers. Their effectiveness was limited, though, in part because few of the men serving had ever drilled or received any formal military instruction. These were the Soldiers who fought and lost the first major battle against Confederate forces at the first Battle of Bull Run in July 1861. In the months that followed the first mobilization, Lincoln, with Congress’s eventual approval, repeatedly called on the states to form new volunteer regiments manned by three-year volunteers. This was similar to the success that the Army had encountered in the Mexican-American war by Federalizing state volunteer units. By August 1861, the War Department reported that 486,000 three-year volunteers in state-formed regiments were in Federal service. Based on advice he received from the commanding general of the Army, Winfield Scott, Lincoln decided to keep the Regular Army, and particularly its officers and noncommissioned officers, together in Regular Army units. It may have made more sense to distribute these Regular Army officers and noncommissioned officers to newly forming volunteer regiments so they could teach the untrained soldiers and officers, but the distaste among the militias of being commanded by Regular Army officers could not be underestimated. Scott’s advice to President Lincoln was indicative of the “professionalist” mindset that held sway among Regular Army officers. For Scott, the key to Union success in the Civil War lay with a highly trained and potentially expanded Regular Army. In a way, Scott was refighting the Mexican War.

The War Grinds on.

As 1861 continued into 1862 and 1863 the Union struggled to keep the Army at full strength with repeated calls to the state governors to form more volunteer units. This on top of an increasing number of casualties created recruiting struggles within the Army. One issue became quickly apparent that the Army had to deal with. What to do with replacements: Should they be used to fill out the ranks of extant regiments decimated by fighting or be used to form new organizations? Many of the state units were left to recruit on their own to refill their ranks, or to give a larger bonus for reenlistments, as many had signed three-year enlistments and were now starting to run out. The more common approach was to create new regiments which had negative consequences: Veteran regiments became too small to be combat effective because of attrition. While the new regiments lacked combat experience and absent the guidance that might have come from veteran officers and men, had to learn how to fight the hard way. By the time they learned their trade, they often resembled the smaller veteran units. Due to the recruiting struggles, Congress would use their authority per the 1792 Uniform Militia Act to draft men into newly forming regiments for federal service. Additionally, the law notably dropped the word “white” from the description of the class of men between the ages of 18 and 45 liable to serve—a deliberate break from the 1792 Uniform Militia Act—and authorized enlisting African Americans and granted freedom to escaped slaves who did labor for the Army or joined its ranks. One negative consequence was that the federal draft provoked violent protests in New York City in the summer of 1863.

Logistics nightmares

It’s fine to ask the states to supply more and more volunteer units, but the next problem is where does all the equipment come from? The Union Army quickly learned at the start of the war that leaving the supply and equipping to the state as the units are raised created a logistics nightmare. Due to the rapid manpower increase and the slowly growing but still limited production capability existing within the North, many states looked to countries in Europe to purchase weapons from. There are accounts of many states bidding against each other in the rush to acquire weapons for their state or acquiring weapons that were badly outdated at exorbitant rates. In addition, as the Union Army was assembled, this craze of weapons purchased created a supply nightmare. There were over 15 different types of small arms ammunition that required supply as well as a varying degree of age and reliability of weapons. This would slowly improve over time as production or purchase of the standardized 1861 Springfield in .58 caliber or the 1858 Enfield rifle in .577 caliber were adopted. As the war progressed weapons advancements would continue to be developed with an emphasis on breechloading and repeating small arms. These would only go to increase the firepower and would eventually favor the Union Army as production was increased to the point where the Confederate Army just simply could not keep up with production of the small arm or the ammunition required to feed it.

Tactics

The evolution of tactics for the Union Army evolved largely due to the introduction of the rifled musket, which significantly increased accuracy and range of an infantry formation. This caused a shift from the traditional linear formations (bringing as many rifles to bear against the enemy as possible in your formation) that the U.S. Army had been using since the American Revolution and had been taught to every graduate of West Point. The combination of the traditional linear formation and the rifled musket led to a much greater amount of time that either side is engaging the other. Essentially increasing weapons range would increase the engagement time from approximately 75 to 100 yards, where two to three volleys would be fired, to an effective range of 300 or more yards and the time that it takes a formation to cross that under enemy fire. Major changes in tactical adaptation would not be seen until 1864 during the battle of Spotsylvania Court House. COL Emory Upton would suggest to LTG Ulysses S. Grant to utilize a closed formation tactic, essentially stacked columns of massed infantry, that would swiftly assault a small part of the enemy line, without pausing to trade fire, and in doing so attempt to overwhelm the defenders and achieve a breakthrough. This evolution would see major change in the use of formations and lead to the greater use of entrenchments and trench warfare. The end of the American Civil War is commonly referenced as a rehearsal for the eventual trench warfare that took place in World War One.

Conclusion

At the conclusion of the Civil War, the Army had increased dramatically in size and, for the most part, had overcome many of its growing pains, finally conquering many of its command-and-control issues. At its largest the Union Army would grow to over 600,000 Soldiers in size which in 1863 would outnumber the Confederates by 2 to 1. The total enlistments in the Union Army, over the course of the entire war, would number 2,672,341. This evidence strongly suggests that the Federal system worked, at least insofar as it enabled the northern states to generate and sustain enormous armies when required. There was a significant time delay between when Lincoln called for forces and adequately trained and equipped units became available, but, up to that point, few had cause to think unacceptable the risk associated with that delay. This is not to say that nothing had changed or needed to be changed: The 1863 Enrollment Act, for example, represented an important change in military policy by moving away from the militia clause and embracing the armies clause as the best means to generate large land forces. Moreover, the common or compulsory militias, which had been the backbone of the nation’s military power at the end of the 18th century and beginning of the 19th, had proved to not be capable of meeting the need in time of emergency. The United States Army had matured and learned from the war and had produced many of the new leaders that would carry it into the next phase of its existence.