The Romans paved roads. Paved roads improve communications, no matter the mode of transportation.
With slaves. Our governments used taxes to subsidize paving roads. They built small sections, and encouraged others to link the sections on their own dime. Paying taxes is sort of indirect slavery. The Romans were up front about it; our government does it like a slow boil. We owe a lot to the Roman Empire, road and rail track widths are based on Roman chariots. The Roman Empire fell apart after a few hundred years, and we seem to be following a similar path.