Operators of nuclear power plants worldwide are “struggling” to adapt to the increasing and potentially dangerous threat of cyber attacks, a report warned Monday. The nuclear industry “is beginning -– but struggling -– to come to grips with this new, insidious threat,” the Chatham House think-tank in London said in a study based on 18 months of investigation. In addition there is a “pervading myth” that nuclear power plants are protected because they are “air gapped” — in other words not connected to the Internet.