Concerning the desperate need for more soldiers for the Confederacy, here is an excerpt from Wikipedia about Oates, who later was Governor of Alabama and served the USA in the Spanish American War:
He fought in the Battle of Gettysburg, leading his troops in a series of charges on Little Round Top, where his brother John perished. This became one of Oates's significant memory of the war, as he believed that if his regiment had been able to take Little Round Top, the Army of Northern Virginia might have won the battle, and possibly marched on to take Washington, D.C. Oates later stated that if even a single additional Confederate regiment had joined the assault, the attack could have succeeded, turning the Union's flank and threatening the entire Army of the Potomac.
His [Col. Chamberlain's] skill and persistency and the great bravery of his men saved Little Round Top and the Army of the Potomac from defeat.
[If one more Confederate regiment had stormed the far left of the Army of the Potomac with the 15th Alabama,] "...we would have completely turned the flank and have won Little Round Top, which would have forced Meade's whole left wing to retire." He concluded, philosophically, that "great events sometimes turn on comparatively small affairs."