Plus computers monitor every remotely important reactor parameter, with all data monitored by quadruple probes, and action only taken when at least 2 probes show something wrong (preventing a single bad probe from triggering wrong safety action).
Three Mile Island and Chernobyl could have been prevented with computers analyzing parameters and all failure modes programmed into monitoring software (for best recommendations).
The only parallel I see in human endeavours in large aircraft, with their triple or quadruple everything.
I also know quite a bit about jet aircraft being a private pilot with instrument ratings and a junkie of large aircraft technology.
I strongly suggest you go learn about this before making some uninformed criticism.
Nuclear power has enough people criticizing it out of malice, please don't criticize out of ignorance.
Russia and other former USSR states did learn a lot from Chernobyl, don't think for a second that they didn't. Plus almost every nuclear plant in the world is subject to IAEA inspections plus national regulatory inspections. After radiation from Chernobyl hit Europe serious countries, it became very clear to the whole world that what one country does with nuclear power matters to every other country when the subject is safety.