The correct figure, for purposes of this discussion, is exports not of ill-defined "Southern products" but rather of strictly Confederate products, which turned out to be: cotton, in 1860 ~$200 million or 50% of US total exports.
Most everything else classified as "Southern products" turned out to have shipped from Union states or Unionist regions of Confederate states.
DiogenesLamp: "But none of this addresses the largest and most significant aspect of this.
The bulk of European trade would have moved to Southern ports, and it would have very badly hurt some Northern Industries and especially New York."
Today about 95% of US trade tonnage goes through ports that are not New York.
Indeed, the entire Eastern Seaboard, from Boston to Baltimore, by my calculation receives only 10% of total US freight tonnage.
And how big of a problem has this caused either average Americans or those amorphous "Northeastern Power Brokers"?
You tell me.
You go to great lengths to deny the significance of the export value because you realize what it looks like if the true contribution of the South is acknowledged.
But does it not occur to you it still looks bad even using your deliberately minimized figures? 20 Million people in the North producing only 50% of the export value while 5 Million in the South are producing the other 50%?
Going all out to drop the real number from 34-25% does not suddenly make the point disappear. It still doesn't make any sense at your lowball number of 50%. (I've got SoCalPubbie up to 65%)
You think your 25-34% reduction in the number exculpates? It doesn't.
Also I don't care what the modern shipping patterns are now, they are irrelevant to what was going on in 1860.