Anticipating US entry into WWII in 1939, the Commanding General of the US Army ordered a large-scale military exercise to be conducted. It took place in a large part of Louisiana and through the Carolinas in late summer and early fall and involved 400,000 men. It became known as the Louisiana Maneuvers.

Jennifer McArdle writes:

Sept. 15 was the start of the Louisiana Maneuvers, a series of four exercises that took place over two separate venues — the Louisiana-Texas border and the Carolinas — with each spanning vast, scarcely populated areas of dense forests, uncharted swamps, and river crossings. The maneuvers can be heralded as a logistical achievement: At no other time has there been such a concentration of man and materiel on U.S. soil. However, their true worth was as a “combat college for troop leading” and as a field laboratory to test and train for emerging operational concepts. Indeed, notwithstanding some adjudicatory, training, and bureaucratic limitations, the mass exercises played a pivotal role in confirming the necessity of deploying tanks alongside infantry as a combined arms force. Anti-tank guns were verified as an effective countermeasure to armored vehicles. Air-ground integration, despite an initial Army Air Corps bias towards high-altitude precision daylight bombardment, was shown to have value. Perhaps most importantly, the Louisiana Maneuvers confirmed — to Americans, allies, and adversaries alike — that a ragtag group of “civilians in khaki pants” had been molded over the previous two years into a fighting army. While not a panacea, the maneuvers, in short, were the denouement of the U.S. Army’s pre-war mobilization.

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A great deal was learned from the exercise and many who became great leaders in the coming war emerged from it including General George S. Patton who became the greatest US General of WWII.

Conducting a similar exercise today would expose our military leadership as the incompetent and inept frauds they are, including the Commanding General, Mark Milley. It would also expose the deplorable state of present personnel, and their inability to operate successfully in the field. Thought it would be virtually impossible to conduct an exercise of this magnitude today, our Republican Congress should order the military to conduct similar, though smaller exercises so the state of our military capabilities and efficiency could be assessed.

There is little doubt in the minds of former military leaders that it would be a monumental failure, a failure for which the present administration bears great responsibility. Unfortunately, exposing this failure would be the only way to convince the American People of the need for a competent government in Washington to address the deficiency and take steps to remedy the deplorable situation. Unfortunately, our enemies are already well aware of the situation and only the threat of Nuclear War has prevented the outbreak of hostilities well prior to today.