> but if you compare it to other countries where the capital IS the biggest city, and where there's always one party/coalition in control of the entire legislative and executive branches...well, they seem to actually function better, on average?

> Does anyone look at how Congress and the Presidency behave in the year 2018 and think, "ah yes, this clearly has the results we want"?

Here in 2018, we have the executive branch, and both houses of congress controlled by the same party. And as you point out, it's not going well.