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The quest for fusion power has been a long one. Sadly it seems that fusion is doomed to be decades away for quite some time. However, fission reactors are a well understood technology. Indeed, fission reactions are much easier to initiate than fusion reactions - fission requires interactions between heavy nuclei and neutrons whereas fusion requires light nuclei to overcome the electrostatic barrier between them. So fission is easier to initiate. However current conventional fission reactors - while efficient and better suited for baseload power than other low emission concepts - are quite expensive. They also produce waste and don't burn much of their fuel sources. Not to mention they require processed fuel that requires larger concentrations of U-235 than natural uranium. So I started thinking. What if we took Inertial Confinement Fusion drivers and used fission fuels instead? Assuming we also used a suitable neutron source, it's likely possible to use natural uranium or even natural thorium by employing fast neutrons. This could lead to more economical fuels than conventional fission reactors. It should be possible to get fairly large burnup rates for the fuel as well, so less waste could be produced per unit of energy than conventional nuclear reactors and less fuel would be required. Such reactors would also be safer than conventional nuclear reactors - meltdowns are completely impossible since a very small amount of fuel is reacting at any instant and the reactions only occur if the driver is operating. It could also be possible to have higher power densities than conventional reactors, so smaller facilities would be required and less shielding mass would be needed. Of course this depends on the size of the facility for the driver but the actual reactor itself could be much smaller. Such reactors could also be more thermodynamically efficient by combining conventional heat engine technology with MHD technology. And compared to fusion inertial confinement fission seems to be more achievable. So it could be more economical, safer, more efficient, lower waste production, and smaller than conventional reactors for a given power output. And compared to fusion such reactors could be possible much earlier. And it could lead to the development of more efficient drivers that could make inertial confinement fusion more practical. Or hybrid systems that use fission to initiate a fusion reaction could be possible. Now for some applications. The first one is obvious - baseload electricity. If such technology is more economical than current reactors it could be competitive with other energy sources as well. If developed as a small modular reactor it could be deployed quite rapidly. The second one may be less obvious but still important, though less likely: propulsion for cargo and container ships. Ocean shipping is responsible for quite a large percentage of pollutants and a decent percentage of GHG emissions, and those emissions are expected to grow substantially over time. And of course the one we're all probably more interested in: space propulsion. This can be done using nuclear pulse propulsion or nuclear electric propulsion. If the power density can be made high enough then nuclear-electric systems may be capable of interplanetary missions with reasonable mass ratios. And of course nuclear pulse propulsion could do the same. Such a system would probably be similar to Mini-Mag Orion but without the Z-Pinch system and without the need for other components that limit the performance of the Mini-Mag Orion system (such as the conductive elements needed for the Z-Pinch). So fast transfers to the outer planets would be possible with manned missions. I can't find much literature on this concept - mostly because the words "inertial confinement" are associated with fusion. But it could work with fission. And it seems that it could have some serious advantages over conventional nuclear reactors. Thoughts?