heavy ion fusion
... that although John Foster long ago described heavy ion fusion as "the conservative approach" to a working fusion reactor, no large-scale system has ever been built?
... that although <a href="./John_S._Foster_Jr." id="mwAzc" rel="mw:WikiLink" title="John S. Foster Jr.">John Foster</a> long ago described <b id="mwAzg"><a href="./Heavy_ion_fusion" id="mwAzk" rel="mw:WikiLink" title="Heavy ion fusion">heavy ion fusion</a></b> as "the conservative approach" to a working <a href="./Fusion_power" id="mwAzo" rel="mw:WikiLink" title="Fusion power">fusion reactor</a>, no large-scale system has ever been built?