These are not engineering failures! It is very difficult to get controlled thermonuclear fusion on Earth!
In Cosmos it is way chosen to generate large amounts of energy, but here on Earth this is very different.
Do you know the concept of triple simultaneity? Well, in order to obtain controlled thermonuclear fusion, it is necessary to simultaneously meet Confinement Time of a few seconds, with sufficient Matter Density and Temperature above 100 million degrees Celsius.
This is not an engineering failure, quite contrary, since the 1930s engineering has advanced enough to build Tokamak ITER, researchers and engineers of controlled thermonuclear fusion have advanced a lot.
However, people think science has to meet its time and it is not so. Understanding and learning about the knowledge of nature needs to obtain technological maturity that is not always available.
To achieve controlled thermonuclear fusion, many technologies had to be developed. We all believe that in 2025 we will have ITER functioning and until 2030 we will have the DEMOS Tokamaks, the first fusion reactors.