No intelligent man--much less the Rebel leaders--was ignorant of it nor of its calamitous proportions.
2.

Had the Rebel leaders within a reasonable time after this matter became notorious made some show of inquiring into and alleviating the deadly misery, there might be some excuse for them on the ground of lack of information, and the plea that they did as well as they could would have some validity.

But this state of affairs was allowed to continue over a year--in fact until the downfall of the Confederacy--without a hand being raised to mitigate the horrors of those places--without even an inquiry being made as to whether they were mitigable or not.

Still worse: every month saw the horrors thicken, and the condition of the prisoners become more wretched.
The suffering in May, 1864, was more terrible than in April; June showed a frightful increase over May, while words fail to paint the horrors of July and August, and so the wretchedness waxed until the end, in April, 1865.
3.

The main causes of suffering and death were so obviously preventible that the Rebel leaders could not have been ignorant of the ease with which a remedy could be applied.