United States Army Reserve in the context of "Megan Ambuhl"

The United States Army Corps of Engineers (USACE) is the military engineering branch of the United States Army. A direct reporting unit (DRU), it has three primary mission areas: Engineer Regiment, military construction, and civil works. USACE has 37,000 civilian and military personnel, making it one of the world's largest public engineering, design, and construction management agencies. The USACE workforce is approximately 97% civilian, 3% active duty military. The civilian workforce is mainly located in the United States, Europe and in select Middle East office locations. Civilians do not function as active duty military and are not required to be in active war and combat zones; however, volunteer (with pay) opportunities do exist for civilians to do so.

The day-to-day activities of the three mission areas are administered by a lieutenant general known as the chief of engineers/commanding general. The chief of engineers commands the Engineer Regiment, comprising combat engineer, rescue, construction, dive, and other specialty units, and answers directly to the chief of staff of the Army. Combat engineers, sometimes called sappers, form an integral part of the Army's combined arms team and are found in all Army service components: Regular Army, National Guard, and Army Reserve. Their duties are to breach obstacles; construct fighting positions, fixed/floating bridges, and obstacles and defensive positions; place and detonate explosives; conduct route clearance operations; emplace and detect landmines; and fight as provisional infantry when required. For the military construction mission, the chief of engineers is directed and supervised by the Assistant Secretary of the Army for installations, environment, and energy, whom the President appoints and the Senate confirms. Military construction relates to construction on military bases and worldwide installations.

The United States Army (U.S. Army) is the land service branch of the United States Armed Forces. It is designated as the Army of the United States in the United States Constitution. It operates under the authority, direction, and control of the United States secretary of defense. As a part of the United States Department of Defense, it is one of the six armed forces of the United States and one of the eight uniformed services of the United States. The Army is the most senior branch in order of precedence amongst the armed services. It has its roots in the Continental Army, formed on 14 June 1775 to fight against the British for independence during the American Revolutionary War (1775–1783). After the Revolutionary War, the Congress of the Confederation created the United States Army on 3 June 1784 to replace the disbanded Continental Army.

The U.S. Army is part of the Department of the Army, which is one of the three military departments of the Department of Defense. The U.S. Army is headed by a civilian senior appointed civil servant, the secretary of the Army (SECARMY), and by a chief military officer, the chief of staff of the Army (CSA) who is a member of the Joint Chiefs of Staff. It is the largest military branch, and in the fiscal year 2022, the projected end strength for the Regular Army (USA) was 480,893 soldiers; the Army National Guard (ARNG) had 336,129 soldiers and the U.S. Army Reserve (USAR) had 188,703 soldiers; the combined-component strength of the U.S. Army was 1,005,725 soldiers. The Army's mission is "to fight and win our Nation's wars, by providing prompt, sustained land dominance, across the full range of military operations and the spectrum of conflict, in support of combatant commanders". The branch participates in conflicts worldwide and is the major ground-based offensive and defensive force of the United States of America.‌

The Regular Army of the United States succeeded the Continental Army as the country's permanent, professional land-based military force. In modern times, the professional core of the United States Army continues to be called the Regular Army (often abbreviated as "RA"). From the time of the American Revolution until after the Spanish–American War, state militias and volunteer regiments organized by the states (but thereafter controlled by federal authorities and federal generals in time of war) supported the smaller Regular Army of the United States. These volunteer regiments came to be called United States Volunteers (USV) in contrast to the Regular United States Army (USA). During the American Civil War, about 97 percent of the Union Army was United States Volunteers.

In contemporary use, the term Regular Army refers to the full-time active component of the United States Army, as distinguished from the Army Reserve and the Army National Guard. A fourth component, the Army of the United States, has been inactive since the suspension of the draft in 1973 and the U.S. armed forces became an all-volunteer armed force.

The 82nd Airborne Division is an airborne forces formation of division-size of the United States Army specializing in parachute assault operations into hostile areas that has remained active since World War I and World War II. The division is commanded by Major General Brandon Tegtmeier. It was officially organized in the United States in 25 August 1917 at Camp Gordon in Georgia, remaining active until 1919, however it was reactivated in 1921, and has now been re-located to Fort Bragg in North Carolina.

The 82nd Infantry Division was the second United States infantry-combat division of eight to leave and arrive in England, and fight in France. The 82nd Infantry Division served with distinction on the Western Front in the final months of World War I. Since its initial members came from all 48 states, the division acquired the nickname All-American, which is the basis for its "AA" (pictured), on the shoulder patch. The Division took part in the Battle of Lorraine 1918, and the campaigns of St. Mihiel and Meuse-Argonne 1918. It was reconstituted into the Organized Reserves as Headquarters, 82d Division, on 24 June 1921 and was then based at the Federal Building located at Columbia, in South Carolina.

The 82nd Airborne Division ("All American") is a United States Army airborne infantry division, that specializes in parachute assault, based in Fort Bragg, North Carolina. Currently, the division is commanded by Major General Brandon Tegtmeier.

It was first officially activated at Camp Gordon, in Georgia on 25 August 1917, though, it would later be demobilized on the 27th of May 1919, at Camp Mills, New York. During the summer of 1921, it would be reconstituted, placed into the Organized Reserves, as Headquarters, 82nd Division, and it would later be transferred to the Federal Building at Columbia, South Carolina. The 82nd Infantry Division was the second United States Army infantry-combat division of eight to deploy and return in England, and fight in France. The 82nd Infantry Division served with distinction on the Western Front in the final months of World War I. Since its initial members came from all 48 states, the division acquired the nickname All-American, which is the basis for its "AA" (pictured), on the shoulder patch. The Division took part in the Battle of Lorraine 1918, and the campaigns of St. Mihiel and Meuse-Argonne 1918.

The 96th Infantry Division was an infantry division of the United States Army. It was formed in 1918 and served in World War I and in the Pacific War during World War II. It was reformed after the war and was part of the United States Army Reserve until 1965.

In 1967 the number "96" was resurrected for a U.S. Army Reserve area administrative headquarters, the 96th Army Reserve Command. Technically it had no lineage connection to the 96th Infantry Division. With a number of redesignations, it continues in service in the 21st Century. Effective 17 September 2008, it became the 96th Sustainment Brigade, with its headquarters located at Fort Douglas, Salt Lake City, Utah.

A corps area was a geographically-based organizational structure (military district) of the United States Army used to accomplish administrative, training, and tactical tasks from 1920 to 1942. Each corps area included divisions of the Regular Army, Organized Reserve, and National Guard of the United States. Developed as a result of serious mobilization problems during World War I, this organization provided a framework to rapidly expand the Army in times of war or national emergency, such as the Great Depression.

The nine corps areas, created by the War Plans Division under authority of United States War Department General Order No. 50 on 20 August 1920, had identical responsibilities for providing peacetime administrative and logistical support to the army's mobile units as was provided by the six territorial "Departments" they replaced. In addition, the corps areas took on the responsibilities for post and installation support units ("Zone of the Interior" units) created during World War I. Corps areas had the added responsibility for planning and implementing mobilization plans for all Regular Army, National Guard, and Organized Reserve mobile units in their respective geographic areas; the development and administration of hundreds of new Organized Reserve and Reserve Officers Training Corps (ROTC) units; and managing the personnel records for thousands of Reserve officers, enlisted personnel, ROTC cadets, and Citizens Military Training Camp (CMTC) candidates.