It's a valid argument that people die because of multiple nuclear accidents in the USA.
In a car accident if someone dies two days after in hospital as a result because of injuries (a consequence of the accident), people say that they died of a car accident.
Radiation poisoning is obtained as a result of a nuclear accident. In exactly the same way as injuries obtained as the result of other accidents.
To draw a distinction, and claim there is a difference is being ambiguous. Many people will misunderstand the difference because it makes no sense, and is not the way everyone else uses the language.
To claim people understanding the statement in a sound way are fearmongering or being ignorant is silly.
The headline is misleading.
ps. "only fatal reactor accident in US history" claim, apart from the other deaths within the USA, the recent (and still ongoing) Fukushima accident used a General Electric design from the USA.