> We (the US) had a very successful, carefully designed system

The idea that it was "very successful" basically comes from ignoring things like the Civil War, and the idea that it was "carefully designed" comes from building a fiction around the output and ignoring the process that actually produced it (in no small part aided by people viewing the after-the-drafting sales campaign of the Federalist Papers as if it reflected a real coherent rationale that went into building the system rather than a marketing campaign developed for a particular audience for an existing product.)