Don't blame the quake and tsunami. Its water did take out the generators needed for the coolants, the plant was wide open for such an accident. NAIIC found the accident to be forseeable and that TEPCO failed to meet basic safety requirements. TEPCO even had two internal studies on the risk of Tsunamis and how to defend against them but management ignored those warnings. If those warnings aren't enough. Japan's coast is full of physical markers from past Tsunamis, indicating the top of those waves and where the safe ground begins.
https://99percentinvisible.org/article/tsunami-stones-ancien...