Funny thing is China most likely going to be the country to solve that as well, Prototype with stable high voltage output is already in the drawing board and probably go online in mid 30s, While ITER is busy with their feasibility studies
it doesn't matter who will solve it first. what really matters is who will first adopt fusion energy fast enough in their country..
you know who is in a league on its own on adoption of technologies? China...
you know how many batshit crazy research projects have been shelved or sitting abandoned somewhere in the drawers due to excessive energy demand? Now imagine unlimited and free fusion energy becoming suddenly available.
it's really crazy it would really catapult human civilization to an entirely new level. Hopefully we can witness this in our lifetimes