Complex sentence: In none of these cases were nuclear weapons used; yet there have been many civilian and military deaths, surpassing the damage caused by the atomic bombings of Hiroshima and Nagasaki during World War Two.
Split into simpler sentences: In none of these cases were nuclear weapons used. Yet, the extent of civilian and military deaths have been considerable, surpassing the damage caused by the atomic bombings of Hiroshima and Nagasaki during World War Two.