This is the beginning of a critique that presents lost opportunities as being Richmond's failures. In fairly routine back-and-forth, it begins to become hard to tell which requests also hold within accusations under the Richmond failure paradigm:
Mr. PRESIDENT: I have suggested, through the Adjutant and Inspector-General, the importance of increasing our forces of artillery and cavalry - … It is certain to my mind that all of Napoleon's successes in 1813 were due to his large proportion of artillery. … May I remind you that I have more than once mentioned our deficiency in cavalry? We have not half enough for mere outpost duty. (Johnston, HEADQUARTERS, MANASSAS, August 10, 1861.)On September 5, in response to what I am unsure, Davis answers Johnston, "I have done all that was possible to strengthen you since the date of your glorious victory."
On Spetember 8, Davis is already responding to "invade the north" suggestions defensively:
… We cannot afford to divide our forces unless and until we have two armies able to contend with the enemy's forces at Washington. Two lines of operation are always hazardous. I repeat that we cannot afford to fight without a reasonable assurance of victory or a necessity so imperious as to overrule our general policy. We have no second line of defense, and cannot now provide one. The cause of the Confederacy is staked upon your army, and the natural impatience of the soldier must be curbed by the devotion of the patriot… [I] wish we could strike him in his present condition; but it has seemed to me involved in too much probability of failure to render the movement proper with our present means. Had I the requisite arms the argument would soon be changed… It is true that a successful advance across the Potomac would relieve other places; but, if not successful, ruin would befall us.On September 26, the day of the meeting, Johnston writes the secretary of war,
… Thus far the numbers and condition of this army have at no time justified our assuming the offensive. To do so would require more men and munitions. We are not now in a strong defensive position either to fight a battle or to hold the enemy in check. The position was occupied for a different purpose. It is now necessary to decide definitely whether we are to advance or fall back to a more defensible line…This note represents the cards he will deal to Jefferson Davis in their meeting.
p.s. "The position was occupied for a different purpose" - We should note that Johnston has moved his army out of Centreville to an intermediate point from which it could launch an offensive or fall back.