Before the interstate system was conceived in the 1950s but after the car was well established, like in the 1930s, could you drive coast to coast in the US without using any unpaved roads? Or was infrastructure for intercity car travel just absolute shit?
It was absolute shit. In fact, a military convoy across the country including a young Dwight Eisenhower - which took TWO MONTHS - was a major inspiration for the interstate system.
There had been previous projects to get more roads built, but rail travel was still the dominant way to get across the country.
If you were traveling by automobile long distance prior to the 1930s you'd have been smart carrying something like this. The roads were sparsely policed and highwaymen operated with impunity