https://www.cnet.com/news/homeland-securitys-biggest-election-concern-is-what-comes-after-you-vote/

The conversation with Nielsen about comes just four days before Election Day and amid major DHS efforts to protect the US elections from foreign interference.

That includes assisting election officials in all 50 states, creating its own center to protect critical infrastructure, and attending Defcon to learn about voting machine flaws. While DHS is working to protect the machines and make sure voting officials are prepared, it's that wave of disinformation on social media that'll follow the election that Nielsen's most worried about.