lightning rod

noun2

1. •
   A metallic conductor that is attached to a high point of a building and leads to the ground to protect the building from damage by lightning.
2. •
   (figurative) A person or thing that is a target for negative reactions and distracts criticism from another target.

   • Another factor was that when the two governments changed Stormont’s rules in 2006 they left the dual premiership as the “lightning rod for other difficulties”, said [Brendan] O’Leary. — 2023