There was a tax levied by Congress on cotton during reconstruction. I can't remember the rate, maybe 4 Cents a pound. The ostensible purpose of the tax was to make the South help pay the costs of the war. Obviously this was a serious hardship in a devastated region like the South. So, clearly, Congress was more interested in punishing the South than stimulating it. It is hard to say where Lincoln's heart was on this issue. Ironically, the people hit really hard by the tax were the many share cropping blacks who sold their own portion of the cotton crop for profit. This also makes it clear that there is no way Lincoln would have had any belief in his compensation plan passing Congress. It really points to it being a gesture of some kind, whether done for cynical or charitable reasons we can only speculate.