The opinion of the Court suggests that the rejection of Stevens’ proposal signified the adoption of the theory that representatives are properly understood to represent all of the residents of their districts, whether or not they are eligible to vote. As was the case in 1787, however, it was power politics, not democratic theory, that carried the day.
The list could go on. The bottom line is that in the leadup to the Fourteenth Amendment, claims about representational equality were invoked, if at all, only in service of the real goal: preventing southern States from acquiring too much power in the National Government.
This is, in fact, accurate. I would strongly recommend Mark Graber’s recent paper, which shows that the framers of the 14th Amendment were largely uninterested in the precise wording of Section 1, and were almost exclusively focused on Section 2. I’ll have more on the implications of his argument later, but it’s relevant here. Their belief, essentially, was that in light of Dred Scott it didn’t really matter how you worded federal civil rights protections if people opposed to civil rights controlled the Supreme Court. If, for example, people like John Roberts and Sam Alito were pivotal Supreme Court votes, no matter how explicit you made congressional authority to prevent racial discrimination in voting in the 15th Amendment, it wouldn’t matter. You have to say they were prescient.
Trying to determine the “original meaning” of the Equal Protection clause, then, is essentially pointless, because the framers recognized that its meaning would depend on court personnel.
This doesn’t make Alito’s conclusion valid, however. If he consistently believed that because the 14th Amendment was the product of power politics and written by people who were not naive legal formalists that the Supreme Court should simply not act to enforce it, that would be one thing, but as we’ve seen he doesn’t. So the Supreme Court should try as best they can to protect the democratic equality that was the central purpose of the 14th Amendment. And this means when state legislatures change the denominator in order to dilute minority representation, it’s unconstitutional.