National population density in the US is misleading. Population density drops off sharply between the Rockies and somewhere around Iowa. East Coast states that we think of as mostly rural, like Virginia and Pennsylvania, have population densities that are squarely within the European range: 110 people/sq km in Pennyslvania vs. 106 in Hungary; 81 in Virginia vs. 82 in Romania. On the other hand, Utah (14) is less dense than Saudi Arabia (16) - both places are mostly desert.

Arkansas has a population density of 22 people/sq km, close to Sweden - but Arkansas is probably much less urbanized.