You keep trying to put forth that argument , and I keep pointing out we can't even control the Southern border we have now. Massive amounts of illegal goods flow across it, and we have better means of controlling it now than they would have then.
And as I have pointed out to you there is a great deal of difference between the transportation of today and the transportation of 160 years ago. What alternative was available to move thousands of tons of imports through the U.S./Confederate border in 1860. By all means enlighten us.