"I would have left that in if I'd had the original text."
You are covering up your intent to publish misleading quotes by acting as if you would have been forthright "if I'd had the original text." The original text is just as readily available as your version, and you are intentionally trying to pass off your quote as valid when it was nothing but propaganda.
Therefore this statement >>> "I do notice that different versions of the quote appear on the Internet" is nothing but a cover up of the fact that you chose a quote that was entirely out of context, and left out the phrase that gave support to my argument.
And here you try again to misrepresent the article: "It doesn't change the meaning and import of what the Mercury was saying"
Of course it does, and you know it.
If you can put someone else on the defensive and wax on and on about some supposed deception, you figure you've "won" in some way. All the better if you get someone else to melt down, or if you simply label their responses "meltdowns." It's all a very familiar game by now.
I put a limited amount of time into these threads now, and rely on what I can find quickly. And yes, it's pretty easy to find the Charleston Mercury saying in 1860 that slavery was a large part of their quarrel with the United States of America. That was more than enough to disprove your contention.
Since then, I have been able to find a text of the editorial. It's here. Notice the first sentences:
The issue before the country is the extinction of slavery. No man of common sense, who has observed the progress of events, and who is not prepared to surrender the institution, with the safety and independence of the South, can doubt that the time for action has come—now or never. The Southern States are now in the crisis of their fate; and, if we read aright the signs of the times, nothing is needed for our deliverance, but that the ball of revolution be set in motion.
That is pretty d*mn*d clear -- virtually unambiguous: "The issue before the country is the extinction of slavery." It's the very first sentence of the editorial, for heaven's sake. There's no possible argument that slavery was very much on the minds of the Mercury's editors. Now about whether slavery was the means to attain or preserve "the safety and independence of the South" or whether "the safety and independence of the South" was aimed at preserving slavery people can argue, but that slavery was very much a part of the picture, that in some way it went to the heart of "the safety and independence of the South" there's not much disagreement possible.
The editorial goes on in the next paragraph (after some material that you can find on the web page):
What is really essential is this—that by the action of one or more States, there shall be the reasonable probability that a Southern Confederacy will be formed. We say probability,—because there is no certainty in the future of human affairs; and in the position in which the South will be placed by the election of an Abolitionist white man as President of the United States, and an Abolitionist colored man as Vice President of the United States, we should not hesitate, somewhat to venture. The existence of slavery is at stake. The evils of submission are too terrible for us to risk them, from vague fears of failure, or a jealous distrust of our sister Cotton States. We think, therefore, that the approaching Legislature should provide for the assembling of a Convention of the people of South Carolina, as soon as it is ascertained that Messrs. LINCOLN and HAMLIN will have a majority in the Electoral Colleges for President and Vice President of the United States.
"The existence of slavery is at stake." That's also pretty unambiguous. Other things may be involved in the "evils of submission," and people can argue about them back and forth about how important they were. But it's clear that the abolition of slavery was among the much feared "evils," and likely that it was the chief "evil" or was the thing that would cause the main or greatest evil.
Notice the reference to Hannibal Hamlin as "an Abolitionist colored man." I don't know if that's a slur or high praise today, but at the time it would have been regarded as a clear attack and a low blow. I thought only Lincoln and the Republicans talked like that, yet here are secessionists -- tolerant and modernly multicultural -- trying to score points with their audience by calling Hamlin "a colored man." What gives? Say it ain't so, squattie! Or were they praising Hamlin after all?
Now let's look at the editorial you cite. It's here. Do you see anything different about it? Hint: it doesn't urge action, it celebrates an action already taken. Hence it doesn't give reasons to drum up support, it simply glorifies the step taken. To be sure it urges solidity behind the secessionist movement, but it doesn't lay out the reasons for secession.
The editorial you cited isn't a rational argument for secession. Rather, it's a breathless account of the secession proceedings punctuated with rapturous rhetoric. You're not going to find out what motivated the secessionists by reading it, you'll just discover how they glorified and mythologized their own actions.
Kobrick may have been in college when he wrote his article, but he writes well, and it looks like he put a lot of work into it. Did you really read his article at all?
Kobrick devotes 4 paragraphs out of 18 pages to the Rawle controversy, or to be generous, 2 pages out of 18. It's not the primary focus of his article at all. It's a controversy that was resolved in 1909, for crying out loud!
After referring to the Rawle matter Kobrick moves on to more significant matters that are still controversial. I'm not sure he's right about those matters, but I doubt any of us is in a position simply to dismiss his effort.