[GOPcapitalist]

If not then wouldn't that mean the state legislatures acted unconstitutionally in seceding, at least as Rawle saw it?

..."as Rawle saw it" being the operative words. This issue was actually debated at length in 1861 with some states concluding a convention was the way to exit the union. Others, such as Tennessee, explicitly rejected that concept and concluded that an act of the legislature was necessary.

[Non-Sequitur]

..."as Rawle saw it" being the operative words.

Rawle also believed that unilateral secession was constitutional to begin with. Turns out he was wrong on that, too.