On September 29, 1789, Congress took a decisive step in shaping the defense architecture of the young nation: it formally created the U.S. Army under the new framework of the Constitution. Though this might seem like a procedural act, its passage marked a pivotal moment in defining the balance between federal power and military oversight in the post‐Revolution era.
Before this formal establishment, America’s military forces were structured under the Continental Army, organized in 1775 during the Revolutionary War. After the war’s end, the Articles of Confederation allowed for a central government to raise troops for common defense, but overall military authority remained weak and diffuse. Under that system, much of the defense burden fell to individual states and militias.
The framers of the Constitution, however, recognized that a stable republic required a clearer, legitimate, and controlled mechanism for raising and supporting a standing force. Thus, Article I, Section 8—the so-called “Army Clause”—granted Congress the power to raise and support armies, with one crucial check: no appropriation for that purpose could last more than two years. This built-in limitation underscored the Founders’ wariness of a permanent standing army, while still allowing the central government to defend the nation when needed.
At the end of the First Congress’s initial session, President George Washington insisted that Congress pass legislation clarifying the army’s role under the new Constitution. In a letter sent on August 7, Washington urged congressional action to replace outdated provisions from the Articles regarding military authority. Despite earlier inaction, Congress responded in its final hours by passing what was called the “Act for the Establishment of the Troops.” That law not only formally recognized the Army but also stipulated that soldiers must take an oath to the Constitution and granted the President authority—under certain conditions—to call up state militias.
At the time of the act’s passage, the federal standing army was modest—about 800 men, including officers. The choice to begin with a small force reflected both practical constraints and philosophical caution about military power. Over subsequent centuries, the Army grew in scope, mission, and complexity, eventually becoming the massive institution central to U.S. defense. As of 2018, for instance, active duty strength had swelled into the hundreds of thousands.
The significance of that September day in 1789 lies not just in creating a military organization, but in embedding the principle that civilian authority—through Congress and the President—would govern the armed forces. Establishing the U.S. Army under constitutional guardrails helped anchor military power within the rule of law, ensuring that the new republic would neither be defenseless nor dominated by instruments of force beyond democratic control.
It was good reasoning on September 29,1789 that established the Army as it was established. This is a very good article praise for all connected with writing it. Growing up in Philadelphia during the 1950’s and 1960’s Independence Hall and the Betsy Ross House, nearby Valley Forge and the site of Washington’s Crossing of the Delaware River – all had an influence on developing a realistic view of American history. I feel fortunate to have had that influence .This article provides a very good summary of the history of the. United States Army.