Fusion power is the technology that is 30 years away, and always will be, according to skeptics, at least. Despite its difficult transition into a reliable power source, the nuclear reactions that power the sun have a wide variety of uses in other fields. The most obvious is in weapons; hydrogen bombs are to this day the most powerful weapons we have ever produced. But there's another use case that is much less destructive and could prove much more interesting—space drives.
source https://phys.org/news/2020-10-spacecraft-titan-years-fusion.html
