Battles, particularly, a Perryville, Kentucky should be remembered more often. But Perryville is more than a vicious draw of two brave armies. It also is on close inspection, a synopsis of why the war went badly for the Confederacy.
Perryville was the last gasp of the Confederacy to greatly control Kentucky. It had later raids, as did Missouri and western Virginia, but Perryville showed a valiant army and an inherent weakness. That weakness was strategic supply problems. A tale of an army out of touch with a supply system and an army that ran out of ammunition and forage, quite quickly.
The Union army could bring more troops to the point of attack, eventually, and keep them supplied.
Perhaps by avoiding the Battle of Perryville, we are allowed for a time to imagine some sort of Confederate victory; a victory the Perryville's would not allow.
The Confederacy could fight once at a Perryville, but never hold it for long.
It was combating a Union army that had supply depots across the northern edge of Kentucky, where the Ohio River layed. The Confederates had no railroads to move supplies inland in Kentucky, and the Union had less distance to travel, from those depots, to combat the lesser sized army fielded by the Confederates.
The Confederacy could never hold Kentucky, despite the bravery of its armies. It had too few supplies, too few effective ways to get those supplies to the small army that received them. It had both the components of victory and the reasons for defeat.
Perhaps it is too uncomfortable to consider that Kentucky was never winable. That the Confederacy could never really imagine, holding all the states represented in their battle flag. Thirteen stars - too far beyond their reach. Even at the beginning.