Liberal anger with the existence of the U.S. Senate is growing. The confirmation of Justice Brett Kavanaugh coupled with the realization that even with a strong performance in the midterms Democrats have relatively low odds to take back the Senate has renewed liberal complaints about the idea of equal representation for low-population states.

In one of the latest examples in this genre, David Leonhardt has caused a stir with a column dubbing the U.S. Senate "affirmative action for white people" because nonwhites tend to be more clustered in states with larger populations, meaning proportionately less representation in the chamber. Ramesh Ponnuru has noted some of the problems with Leonhardt's accompanying proposal that D.C. and Puerto Rico be added as states to even things out. But I have to say this tweet from Harvard Law School's Laurence Tribe, calling the Senate "a key part of our Faustian bargain with the evil of slavery," really stood out as particularly bizarre.

There are, to be clear, sadly too many examples of moral compromises that were made by our founding generation that preserved the evil institution of slavery. We should not be ever lose sight of it, or fail to recognize that we're still suffering as a nation today as a result of bargains struck over slavery. But it seems to me as bizarre to point to the creation of the Senate as being a "key part" of that bargain.

The battle over proportional representation versus equal representation was a matter of small states versus big states — not a battle of states which had fewer slaves versus states that wanted to preserve slavery.

In fact, the state most passionately advocating for proportional representation (and against giving smaller states an equal vote) was Virginia — which also happened to be the largest slave-owning state, by far. According to the 1790 census, Virginia had 292,697 slaves, or about 42 percent of the national total. Yet the Virginia Plan for the new government called for two legislative houses, both of which had population-based representation.

During the Constitutional Convention, Virginia found allies among representatives of other large slave states including South Carolina (107,094 slaves) and North Carolina (100,572 slaves). Some representatives in the Deep South believed that proportional representation would benefit them over time due to the region's rapid population growth.

Of course, Virginia's biggest allies in the battle were the big states of Massachusetts (zero slaves) and Pennsylvania (3,737 slaves). So again, slavery was not the dividing line on the equal versus proportional representation issue. It was about smaller states and larger states arguing over their influence.

Furthermore, there's actually an argument that a strictly population-based system of representation would have done more to preserve and expand slavery. The reason is that under the infamous three-fifths compromise, 60 percent of slaves counted toward the population used in determining representation. Yet, because slaves were granted no rights, in effect it meant all of their representation flowed through their masters. In a purely proportional system, this would not only give relatively more power to slave owners, but provide an even stronger incentive for importing and keeping more slaves, and states with large slave-holding populations would have yet another reason to want to encourage the practice.

So, it seems kind of weird to point to the Senate as an institution that was central part of the bargain to preserve slavery.