Perhaps, though such a conclusion assumes what those costs happen to be. Without knowing them though, it is impossible for you to say for sure.
And if you send those goods to Charleston to avoid the tariff in New York then what do you do with them?
Ship them around the continent internally. That means ship them by rail to North Carolina and so forth. Or ship them up the mississippi from New Orleans and so forth. It's a lot harder to collect tariffs on goods travelling over land than by sea at the port of entry.
How will Charleston be a way of accessing the North American continent?
Well, the last time I checked, Charleston was not located in Argentina, nor France, nor Nigeria, nor Japan. It was located on the coast of South Carolina, which is on the North American continent.
Seems to me that the stuff will just sit there and rot
Why would it have any reason to sit there? If buyers up north knew they could get goods without a tariff by going to Charleston, economic law dictates they would go to Charleston. If they knew they could get the same at New Orleans, they'd go to New Orleans.
Because if you're suggesting that those goods will be sent to Northern states then that makes no sense at all. Why ship goods to Charleston, pay the confederate tariff, tranship them to the North, and pay the Northern tariff as well plus all those additional shipping costs?
Because that would not be done. Unless Lincoln established inland customs houses all up the Mississippi and at every road and railway across the border from Virginia and Arkansas, goods could enter the south, paying only the low southern tariff, then be transfered up north by inland means without any further taxation. I suppose it would technically be "illegal" to do so, but without a mechanism to enforce the northern tariff, it simply won't be collected.
Sure, ship them up the interstate. The Feds can't cover all of them, can they? </sarcasm>
Looking at a map of the railway system in the U.S. around 1860 would indicate that there weren't that many lines connecting the North and the south. Make them two countries and it wouldn't be hard for the government to limit the available crossing points and slap a tariff on the goods as the came across.
If buyers up north knew they could get goods without a tariff by going to Charleston, economic law dictates they would go to Charleston. If they knew they could get the same at New Orleans, they'd go to New Orleans.
But if the buyers up North knew that the goods would be hit with a tariff as soon as they brought it up North then why would they want to pay the confederate tariff, the U.S. tariff, and all the associated transportation costs?
Unless Lincoln established inland customs houses all up the Mississippi and at every road and railway across the border from Virginia and Arkansas, goods could enter the south, paying only the low southern tariff, then be transfered up north by inland means without any further taxation.
Every road? How much travelled by road in those days? You're talking railroad and river only, and it wouldn't be hard to limit those crossing points and add the tariff to goods coming across.