The problem isn't building them it's operating them. This is not a technical problem and there can be no technical solution to it.
If you have the access and ability to safely operate a nuclear reactor you also have the access and ability to operate it very unsafely if you choose to. There is no way around this that doesn't also remove your ability to operate it safely.
Your second paragraph is phrased as a fact, but it's an opinion. It's probably true today, but it can't actually be a factual statement, because we don't know what we don't know.
If you have the access and ability to safely operate a nuclear reactor you also have the access and ability to operate it very unsafely if you choose to. There is no way around this that doesn't also remove your ability to operate it safely.