Then how did the UCSA increase it's IC/turn under Dldnjstjr?
It invested in China, which I mirrored, which had absolutely no effect.
I tried doing the Sherman Anti-Trust Act too, which also had no effect.
I believe I tried many other things too, conquering Arabia, adding Korea, adding Luzon, attacking Vietnam, purchasing lands, all of which was fruitless and had no effect.
Meanwhile, I see in this update that the UCSA's purchase of land has increased its IC/turn by two.
I'm either missing something completely or I'm just completely stupid.
EDIT: In fact the only thing that I did that ever increased my IC was the unification of Belgium and the Netherlands.