Scientists at a laboratory in England have shattered the record for the amount of energy produced during a controlled, sustained fusion reaction. The production of 59 megajoules of energy over five seconds at the Joint European Torus – or JET – experiment in England has been called "a breakthrough" by some news outlets and caused quite a lot of excitement among physicists. But a common line regarding fusion electricity production is that it is "always 20 years away." We are a nuclear physicist and a nuclear engineer who study how to develop controlled nuclear fusion for the purpose of generating...