And just imagine the infrastructure we could have had for the cost of the Iraq war + the bank bailouts!
Anyway one thing I'd like to mention that never gets highlighted is that buses are BY FAR the cheapest public transportation solution. Its not sexy but the good old fashioned bus is great since it can use the road infrastructure already built whereas trains need right of way and a lot of construction before they can be used.
You're right that new bus routes have a very low marginal cost, and that buses move more people per transportation dollar than other forms of public transportation, but without expensive dedicated lanes they are certain to be slower than cars, and therefore most otherwise merry takers of public transportation avoid using them.
Another unfortunate problem with buses is that changing the bus route is pretty much trivially easy, with the consequence that they do change an awful lot (at least here in Boston), which means that buses generally provide really unreliable transportation.
Montreal has a great bus system, iirc. Dedicated roads, dedicated, clean, underground tunnels. Probably super expensive. Alas.
Granted it might be hard to sell a rail project like the space race, but looking back on just how much of our GDP we where spending to play golf on the moon was insane.
I'd argue the USSR was the imminent threat. According to wiki, Khrushchev openly & repeatedly threatened the West with nuclear annihilation. The space race was a bid to regain technological supremacy after sputnik.
Also back then it wasn't clear that it would be just the one trip.
I used to travel by bus instead of train all the time when I was in Thailand because the bus was always faster and cheaper than the trains. The only way trains are better is if they are much faster than buses.
High speed train is more of an alternative to flying then to buses. Taking into consideration time spent to get to/from the airport, security checks and occasional delays, trains are better under 1000 km, and may be worth it for a lot more.
Eurostar checks are very tight and even on busy days it won't take over an hour of queuing at Gare du Nord. Usually there aren't so many trains to board so it's much easier to organize. I suffered a whole station lock-down on a busy Sunday night due to a large piece of luggage left near the security checkpoint. It delayed my trip only 2 hours, including the delays of not being on time for the cleared route. Another thing is trains don't usually have busy schedule of airplanes so they usually wait for people if something like that happens.
Also there's no fuel around to use as explosive material.
Spain had its share of train terrorist attacks, and at least in the rest of the Europe you can't tell. I don't know about inside Spain, though, but I imagine it's still not much difference.
To make buses work in a modern city, you need dedicated bus lanes. Mexico City has em, and they are amazing. Without bus lanes, buses suck for inner-city travel. They are slow, and traffic sucks.
Anyway one thing I'd like to mention that never gets highlighted is that buses are BY FAR the cheapest public transportation solution. Its not sexy but the good old fashioned bus is great since it can use the road infrastructure already built whereas trains need right of way and a lot of construction before they can be used.