Yep.

Even the fastest trains Amtrak offers ("Acela") are zoned - or permitted, not sure what the right term is here - up to 150 MPH, and only on specific portions of the route.

Makes no sense at all.

The sense is that the Northeast corridor has too many curves and roadbed issues to be able to go faster.

There would have to be constructed a new corridor, not in the same path as existing railroad rights of way, for not a small amount of money, and going through expensive real estate.

The political will for that is not in existence, so far.

And the fact is that while taking a train the full length of the Northeast Corridor takes too long to be practical most of the time, NYC to points north and NYC to points south works pretty well (i.e. is competitive with flying) with existing trains.

Easy to complain on the internet. Hard to change a hard left into a sweeping arc in the middle of New Haven.

Even ignoring the money, if you try and do a project like that you are going to get slapped in the face by all the same "cutting apart muh neighborhood" rhetoric that gets used against highways. Grade separation and "just paying those people to go away" are both expensive enough to be non-starters.

Highways and rail create different kinds of disruption in neighborhoods. Highways constantly have traffic, creating noise and pollution all the time. Railroads are mostly quiet, with loud traffic in short bursts.

Passenger railroads are narrower than urban highways. The US-101 freeway cuts through Echo Park and Westlake in Los Angeles, taking up as much as 330 feet of width, counting on/off ramps. California HSR has trench sections specced as narrow as 72 feet[1], and most of its urban rights-of-way are under 100 feet wide.

Walking next to the 101 in Echo Park you can see how it so starkly divides what was once a single connected neighborhood. The light rail lines (about ~40-50 ft to cross) in other neighborhoods don't give that impression.

[1]: https://www.hsr.ca.gov/wp-content/uploads/docs/programs/eir_...

I have no love for highway pits but to play if off like an HSR pit is some quaint little light rail is simply farcical.

You're being dishonest or ignorant. The fact that you compare max-width of one to min-width of the other rules out one option. A pit is a pit. You're limited to crossing at a few specific points no matter how narrow it is and traveling to those points accounts for the bulk of the distance covered. The physical width only matters if you're evaluating the neighborhood for visual appeal and not actual livability. "Quiet most of the time" doesn't really count for much because people acclimate to the background noise levels and that one train per hour is just as jarring as that one motorcycle with the insane exhaust per hour. At least with subways and airports it's every couple minutes so you get more used to it.

High speed rail is like having a jet plane go by, given the intent to run at, say 150 to 200 miles per hour, and has its own troublesome neighbor issues.

All corridors are troublesome.

I regularly travel Tucson <-> Ft. Lauderdale. 2100 miles. Including ground transport, door to door is 10-12 hours.

That's interesting. You must have some much better train routes out in the big empty spaces in between. What line is that?

For me, in DC, the trip is half the distance (1,000 miles) and would take twice as long (25 hours, according to Google).

10-12 hours door to door if flying.

It is 32 hours if driving 130-150 kph on the freeway (80-90 mph) without stopping for food, bathrooms, gas, or sleep. It's probably a few hundred hours with the train since you will have to go a few hundred or a few thousand kilometers north first.

Interestingly, there is a long train line from Louisiana to Los Angeles called the Sunset Limited. Up until Hurricane Katrina in 2005 it ran between Orlando Florida and Los Angeles,

That line is Southwest Airlines.

Wow, crazy! On Amtrak?

On Amtrak, that's a 102 hour trip that takes you through Chicago and DC. Not an exaggeration. Given usual delays, that 102h is wildly optimistic. Coach seats: $387.