I've never been to the UK, but I believe your population density is a lot higher than that of the US; which is where all of our costs originate (interconnecting the customer to our network).
The main reason I can see is that Comcast (or cable internet) has no real competition. I don't understand why that is. AT&T, Verizon etc seem to have given up on competing. Verizon stopped their rollout of FTTH a while back nearly entirely, though it has restarted very slowly.
AT&Ts VDSL based UVerse solution is way too sparse, with very long cable runs. Compare this to BT in the UK where most VDSL2 runs they are doing are <500m. They're now looking at GFast to push fibre even closer to customers, getting copper runs down to ~200m.
Ok, so this may be caused by low population density, but I'm not entirely convinced. It must be way cheaper to dig trenches in suburbia USA as many of the places don't even have sidewalks to dig up and then expensively refill, you could just trench along the side of the road.
The Telco can offer a few things like fiber connectivity between county buildings, tax payments, etc. By doing that, they secure the rights to the area. Given the federal system of the United States, this is a difficult thing to stop.
This makes true market-based competition within most areas very difficult to achieve.
They do not do that. It's illegal under federal law. Pole and conduit owners are required to rent out access at non-discriminatory rates: https://www.law.cornell.edu/uscode/text/47/224.
The reason companies don't overbuild is because it's expensive and there isn't any return. FiOS came to my building in Baltimore. I was the only person on my floor to switch away from Comcast. Even these days, people choose their broadband provider based primarily on the TV package.
But they most certainly can impose enough bureaucracy and other hurdles to make renting factually impossible. Or simply both the incumbent provider and the county employ just a single FTE (or less!) to handle permits, and one can't do anything about it. All while following the letter of the law, because there's nothing in the law that says "county has X days to deal with the permit else it is being automatically granted".
Nothing in the US is "easily" litigated, especially not when you're up against a multimedia conglomerate and a portion of the government itself.
Those two words do not go together.
They definitely do. Our city has a franchise agreement with the incumbent cable provider; they're the only company allowed to provide cable television service. ~10 years ago a company called NuNet tried to come in and run fiber in a neighboring city, Hazleton, and both they and the city were sued by the incumbent for breaching the franchise.
I imagine there are some 30-year exclusive franchises granted in 1991 that are still in effect. I don't actually know of any.
Was FiOS much cheaper/better than Comcast (apart from the underlying tech)?
In the US AT&T and Verizon seem to have given up and want to just do cellular to make money and let their copper plant rot. They are gifting the entire market to Comcast et al.
Cost of the Telcom union, employers and pension adds up, not to mention infrastructure.
They avoid all this by wireless voice, cellular communications.
Still under the FCC though.
I think this is definitely a factor - but it's vastly overstated. The USA is more urbanised than many European countries at 80%, so there's definitely quick wins for the vast majority of the population.
The big difference I see is the way these services are regulated. In the UK for example, the physical infrastructure associated with the last mile is owned by a company that just manages this, with regulated prices linked to asset investment required. Services are then resold to Internet Service Providers who provide the IP services and compete on price and other factors.
The capital costs of providing the infrastructure are restrictive and the advantage of competition does not outweigh the cost of having multiple last-mile infra.
Note - I've used some simplifications on the ownership and extents of infraco/telco ownership, but the concept holds.
Even if you live in an urban area, the prevalence of rural areas (and poor urban areas), has an impact on you, because the US supports rural telecommunications through various internal cross-subsidies instead of direct support.
The regulatory regime plays a role too, but it's more complicated than your simplistic presentation. In the U.K., the last mile infrastructure is owned by a single company (BT Openreach), but equally importantly, the government ensures it is a quite profitable company. Much more so than American utilities. That was a conscious part of the BT privatization: designing a rate structure that would ensure prices high enough to create adequate incentives for investment.
Unfortunately, this kind of thing is rare here.
Plus y'know you can blow fibre to 90% of the population in a reasonable amount of time.
As another point of reference, I live in semi-rural Canada about an hour from a major city and have 150/150 fibre for CDN$85/month.