Both
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If the states did leave by secession, then obviously their votes were not required to enact the additional amendments.
Yes they were, as the the south was forced back into the Union in 1865 and the 14th was [supposedly] ratified in 1868.
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Common law notions of civil contracts do not apply, and merely wanting something someone else can give you does not amount to “compulsion” in any event.
Source, please.
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Requiring the rebel states, either successfully escaped from the Union or not prior to their occupation, to have their legislatures endorse the new amendments as a condition of regaining their forfeited Congressional representation was not compulsion unless you believe that states which had announced their secession had a right to continued representation in the Union they claimed to reject.
It was the federal government that refused to acknowledge the South could leave, thus [according to the Federal government] the right to representation was never interrupted. Are you saying the government could put conditions on the South for an act that never happened?
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Blackstone’s opinion, while of historical interest, will not by itself overturn Supreme Court precedent.
Why should it? Particularly since the Supreme Court didn't have the legitimate jurisdiction to decide the issue in the first place:
However true, therefore, it may be, that the judicial department is, in all questions submitted to it by the forms of the Constitution, to decide in the last resort, this resort must necessarily be deemed the last in relation to the authorities of the other departments of the government; not in relation to the rights of the parties to the constitutional compact, from which the judicial, as well as the other departments, hold their delegated trusts. On any other hypothesis, the delegation of judicial power would annul the authority delegating it; and the concurrence of this department with the others in usurped powers, might subvert forever, and beyond the possible reach of any rightful remedy, the very Constitution which all were instituted to preserve.
James Madison, Report on the Virginia Resolutions
Once you’ve forfeited your representation, you, not surprisingly, don’t get to participate in future debates about when you get your representation back.
The fact that the South came to regret secession did not amount to a moral or legal obligation to readmit their representatives as soon as the last gunshot died away.