First Cav.

This is coolbert:

The American First Cavalry Division during that period of the Second World War retained state-side for some period in the aftermath of Pearl Harbor and not deployed overseas in an expeditious manner for what was apparently good reason to the Pentagon planners.

"The reason that the Army had a continuing interest in horse cavalry operations in 1942 was simply that there was no fully developed strategy for fighting the war in the event of an invasion of the western hemisphere. If the Army, in a tactical situation such as the invasion of France by Germany, could have been guaranteed networks of good roads, ample fuel supplies, gentle familiar terrain and constant air superiority, it might have decided to get along without the horse cavalry operations. However, chances were, that the US defenses might be challenged on less than ideal terrain; perhaps an enemy landing in Western Mexico or along the coast of Brazil, that was friendly to Germany. In such an event mounted soldiers, using sturdy, sure footed-horses, could prove invaluable."

An "enemy landing" on the west coast of Mexico I presume to be the Japanese. An "enemy landing" on the Atlantic coast of Brazil I presume to be the German. Possibility of such events transpiring low but not to be totally precluded from war plans.

"An important operational factor of the horse cavalry was that it could quickly get around and over hazardous terrain such as hills, rocks, trees or desert, but the majority of actual enemy engagement is done fighting dismounted. On such ground, supported by its own artillery and armored units, the 1st Cavalry Division could lick its weight [???] in enemy tanks."

Cavalry also to a large degree while in the field self-sustaining, foraging freely! There is advantage to this!
     
"Near wartime 'full strength' levels, the 1st Cavalry Division was equipped with one hundred forty-five armored reconnaissance cars, six hundred trucks of all sizes, and three hundred seventy motorcycles along with thirteen light tanks. Horses combined with the pool of vehicles could pull or carry a complete mobile arsenal "

At the insistence of Mac Arthur, the division relinquishing all horses when deploying to the Pacific theater.

coolbert.