The ugly truth is that the means of capturing the power really isn't the major hurdle to ITER. If you can get better than breakeven fusion in a containment vessel that won't be broken down by sputtering from fast neutrons, with the densities and temperatures you need for longer than a microsecond or two, all while breeding your own tritium, that would be the miracle. Unfortunately ITER has not come close to that, and really no one else has either .