Your claim -- if it is indeed your claim -- that Lincoln was primarily motivated by his desire to collect duties from Southern ports is ridiculous and contradicted by all evidence of where US duties were collected.
Your statement -- if that's what you've said -- that Southern cotton, aka King Cotton, was in 1860 the US number one export, that's certainly true.
But it was not our only export, and any relationships between exporters and importers was more complex that just saying, "Southern cotton growers paid half of all import duties," as my post just above shows.
"Where" US Duties were collected is quite irrelevant to the point. Where duties are collected says nothing as to who ultimately pays for them.
Lincoln was also not as concerned about "Where" such duties would be collected as he was that they be collected. Again, PeaRidge posted material that seems to indicate the Union was in a serious deficit condition at the start of the war.