There’s a couple reasons why we see so much overhead in the US compared to Europe. One reason is because commercial electric service developed here first, and because of rapid industrialization and urbanization there was a big push to get electricity to everyone as fast as possible. Because of the distances to cover between cities and towns, that lead to overhead transmission and sub-transmission lines, and even overhead distribution lines within cities either because it would slow down installation or because of ordinances preventing utility companies from digging up streets (originally intended for gas, water, phone, and street railway companies). The spread out suburban nature of our cities hadn’t really occurred yet in the late 19th and early 20th century when the electric grid was first being built out, although our cities still tended to be less dense than their European counterparts due to excessively wide streets and a penchant for single-family houses (ersatz farmhouses).
Another thing is that Americans tend to be a bit less civic minded as far as aesthetics are concerned. Our comparatively ugly architecture, harsh and unpleasant public spaces (most of which come in the form of streets that have since been devoted almost entirely to automobile use), and more of a fetishization for mechanical and industrial quantity over quality, or function over form, means that power lines are, to most people, inoffensive enough to not be bothersome. Plus our more generous streets, a product of the industrial aesthetic at the time the US was settled and developed, allow more room for utility poles and also increase the cost of undergrounding simply due to the fewer number of people per feet of wire or conduit served.
Another factor is the type of secondary electrical distribution used. Since the US was one of the first to develop an electrical grid, we standardized on the 120/240 volt single-phase secondary distribution voltage which serves individual customers or a small street. This was an easier and safer voltage for early systems, but it’s limited in its reach from the transformer to only a few hundred feet at most. This means more transformers are necessary which need cooling and serviceability and all that. Europe’s grid, which was developed a bit later, or completely bombed into oblivion and rebuilt anew after WWII, uses a 240 volt 3-phase secondary distribution network, which can have a single transformer serve an entire neighborhood within about a mile. This means simpler wiring and fewer devices, so it’s easier to bury.
Japan is an interesting comparison in that they tend to have small European medieval scaled streets, as well as a pretty sophisticated aesthetic preference, yet their electric and telecom wires are nearly all overhead. They also tend to be somewhat of a rat’s nest as well, which seems surprising considering how thoroughly much of their built environment is cleaned and kept up. My understanding is that this is because of their frequent earthquakes, and with most heating and cooling done via electricity, it’s more important to get the grid up and running again, and that’s easier if it’s overhead.
One thing I do wish was considered more often is a middle ground between full undergrounding and the typical US strategy of horribly disorganized wooden poles with wires strung willy-nilly all over the place. One strategy, which is very common in Chicago and parts of Indianapolis, is to run the utility lines behind houses, either along the alley or a rear easement. Street lights are still an issue, and it’s not easy to retrofit, but it helps the street immensely. Another idea is to use some craft and creativity to clean up the overhead install. Denmark is a famously design-oriented country, and their overhead wiring installations, found in rural and lower density suburban areas, are meticulous. I love how they cross the perpendicular wires over the street to terminate them (note that Denmark is a bit of an anomaly in that rather than using a 4-wire system with the 4th wire being a combined ground/neutral, they use a 5th separate ground wire on the bottom, which you can see is a bit thinner than the others) Google Maps The service drops to individual houses are also very neat and tidy, and those are all done underground from the pole. Google Maps The same thing in the US would look like this https://goo.gl/maps/XFAySSG2gBM2 Even in a more built-up area it’s possible to do it cleanly. http://jjakucyk.com/denmark4.jpg
It’s interesting that in both those Denmark examples only the electric wiring is overhead, whereas I don’t see any telecom or other wiring. Even here in Cincinnati which has painfully little underground electric, pretty much all the telephone lines are buried, although cable TV which came later is not. Telecom lines don’t need all the extra insulation that electric wires do, and they can be closer to one another and to other things as well, so electric is the most expensive wiring to bury. Of course, that expense pales in comparison to the cost of gas, water, and sewer lines, so all the whining about the expense and difficulty of burying the power lines is rather disingenuous.