Nanomaterials often undergo unusual mechanical deformations compared to their bulk counterparts when irradiated with ion‐beams. This study visualizes and investigates some of the unusual interactions that can occur in nanomaterials during irradiation with medium‐energy ion‐beams using a helium‐ion microscope (HIM). Ion‐beam sculpting of semiconductor nanowires (NWs) with sub‐10 nm features is demonstrated. Moreover, irradiation‐induced growth of NWs at room‐temperature is discovered. The new concept and possible mechanism of irradiation‐induced VLS (vapor–liquid–solid) growth of NWs is introduced. These results are the basis for further fundamental and technological developments toward manipulation and visualization of ion–matter interactions at the nanoscale.