It's the truth.
The original attempt by Calhoun to push a high tariff was an attempt to defeat the tariff by making it unacceptable, as you correctly note, because the Southern states already had too few votes to stop it. If you have another method by which a numerical minority can try to win a vote other than by getting people on their side somehow and increasing their tally, I'd like to hear it. A straight vote on what the New England states proposed was certain to end in defeat for Southern opposition, so attempting to find more votes against the tariff is a rational political move to make under those circumstances.
Without a compromise in the Senate, there would have been military conflict of some sort. Neither side was backing down.
I would suggest a reading of
The Road To Disunion: Secessionists at Bay, 1776-1854, Freehling, chapter 15, The First Confrontation Crisis, II: South Carolina versus the South, pg. 281-286, with special emphasis on pg. 278:
"...But those who saw Jackson as conducting government by temper tantrum missed the secret of his killing force. In his every confrontation, the tempestuous Westerner had been the iciest plotter. For all his image as a hothead, Jackson usually fired the second shot. He allowed the enemy to spend initial fury. He then cut aggressors down. He won the Battle of New Orleans that way, and the Bank War, and his most famous duel. The counterpunching warrior now plotted to turn the brainy Calhoun into the provocative assaulter..."
I don't call a compromise when one of the parties cave to almost every point of the opposing faction, as Calhoun did to Jackson and Clay.
Jackson's firmness and Clay's deft negotiations left Calhoun desperately trying to reverse nullification.
Read the above and see if it gives more information on this so-called "compromise."
These actions helped delay secession and made the South wait, as it realized it could neither force nullification nor secession without the support of other states who found little to support in SC's efforts.
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