Back when I was young, the Space Age was the Future, not the Past.
Literally. For the record, the Space Age is 1950's to 1990's.
After the Space Age, we got the Information Age, with the advent of the Internet.
And the abandonment of Space Travel. They lined up really well.
The start of the Space Age was the fallout of WWII. During WWII, Germany has the most advanced Rocketry programme in the world. Wernher von Braun was the father of modern Rocketry. He wanted to go to the moon. The Nazis agreed to fund him, but only if they got to point the rockets at England.
At the end of WWII, both the US and Soviet Union rushed to lay claim to the German intelligencia, and the US has the great power or promising the US instead of Soviet Russia. Soviet Russia was... without getting into it too much, they declared war on farmers, starved to death, and then put an insane idiot in charge of science, and anyone that challenged him was shot.
The second major event was the cancellation of the CF-105 Arrow by A. V. Roe Canada. This was a fighter/interceptor that would be better for Canadian requirements than any existing fighter. And it was cancelled in 1959. A consequence of the cancellation was the destruction of 1/3 of Canada's industrial sector. Guess where they went?
So, the US got a second wave of the best engineers in the world.
Early rocketry was... extremely, extremely crude by modern standards, or should I say artisanal? Modern rocketry has extremely precise computer modelling, which is then manufactured as close to the computer models as possible. Back in the day, rocketry was all made by hand, with everything being interactive. This means that when the knowledge is lost, it's lost forever. All of the rockets used during the Space Age are now lost technology.
First off, what makes a rocket? As distinct from a jet? Rockets have their own oxidizing agent. Jets used the natural oxygen in the atmosphere.
Different atmospheric pressures needed different nozzles. What they came up with was the Multistage Rocket. The rocket was built in several separate stages that were stacked together. The bottom stage would burn until it burns out, and then it was dropped. This would allow the next stage to have a nozzle for it's level, while also dramatically reducing the weight of the following sections.
This worked, and worked well, but this meant millions of dollars of hardware was just cast off every - single - launch.
There was a dream, single-stage to orbit spaceplanes. Spaceplanes could - glide - back to Earth, allowing the entire craft to be reused.
They didn't quite get there, but the Space Shuttle was built in four sections.
The Space Shuttle itself, a colossal fuel tank (hydrogen + oxygen, which is extremely energy dense, and yes, technically makes the space shuttle a steam engine). Then two solid fuel rocket boosters were added. This wasn't perfect, but it was a generational improvement over previous rockets.
We also got the Canadarm, because Canada designed the arm used to maneuver pretty much everything in space.
Of course, the Space Shuttle was never meant to last forever. The forces involved are incredible. And they weren't building a new ship every - single time.
So, they worked on the replacement for the shuttle, the VentureStar. The VentureStar used aerospike engines, these are engines that use the atmospheric pressure to control the plume size, effectively creating auto-adjusting rocket nozzles. With this, there was no longer a necessity to use multiple stages. The entire thing could work as a single-stage to orbit space plane that runs on hydrogen and oxygen.
Making them more environmentally friendly than electric cars.
So, what happened to the VentureStar? We never saw them, so, they didn't work?
Not in the least. They had fully functional, somewhat smaller scale test models making suborbital flights. Suborbital is a ship that reaches space, but doesn't reach a stable orbit, and as such, will inevitably plummet back to Holy Terra. This means that it suffered all of the stresses of the flight, without the risk of it just sailing off to space.
What happened, was much like the Arrow, it was simply - cancelled.
And then space shuttles started blowing up. Well, not the shuttles themselves, but their booster rockets. Still, killed everyone.
So, how did the US react to this? Find another way to get to space?
yes and no. The US - hitchhiked - with Russia. And, until SpaceX, this was the primary way the US got to space.