Given the catastrophe risk involved in their use, there is much to be alarmed at simply to consider the possibilities of accident use - miscommunication, false alarms, broken technology, etc.

It takes more than one thing going wrong at the same time, for an accident to happen, but that happens - that's why we have car accidents - only here we're talking about a potentially civilization/climate ending accident.

Better not to be in that situation in the first place.