Things will go wrong and mistakes will be made when Americans head to the polls in November, but that doesn't mean the election is insecure, the head of the Cybersecurity and Infrastructure Security Agency said Wednesday.

CISA Director Jen Easterly said US elections are incredibly complex, with an estimated 150 million voters expected to head to the polls on Nov. 5. And it's inevitable that there will be problems, whether it's a poll worker forgetting her key, a big storm or even a cyber attack.  

But while those problems will be disruptive, they won't affect the security and integrity of the vote casting and counting process, despite what America's foreign adversaries will claim in attempts to undermine it, she said.

"We should expect that, we should prepare for it, and Americans should not allow that," Easterly said. "It's really up to all of us to preserve democracy."

Easterly made the comments during the opening keynote panel of the Black Hat conference in Las Vegas. The annual event brings together thousands of hackers and other security officials from around the world. 

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Election security has been a major topic for the past two presidential elections. Much was made during the 2016 election about the possibility that a foreign government, such as Russia's, could "hack" the election, either changing results and winners without anyone knowing or changing them to be so obviously improbable that it would destroy trust in the system.

But little evidence of meddling was found, and over the next four years many states shored up their systems and replaced the kinds of voting technology that experts were worried about.

There were worries about potential hacking ahead of the 2020 election, but officials found no evidence of any kind of widespread election fraud. Chris Krebs, then the director of the Cybersecurity and Infrastructure Security Agency, the federal agency charged with protecting the nation's critical infrastructure from cyberthreats, declared the 2020 vote the "most secure election" in American history.

But that didn't stop former President Donald Trump from claiming that it wasn't. To this day, he and many of his supporters continue to falsely claim that the 2020 election was fixed despite the absence of any evidence.

Easterly and the other panelists, who included Hans de Vries, chief cybersecurity and operations officer at the European Union's Agency for Cybersecurity, and Felicity Oswald, who leads the United Kingdom's National Cyber Security Centre, didn't mention Trump during the event, instead focusing on external nation-state threats.  

Regardless of whether the US is attacked by technological means or by disinformation operations, Easterly said state and local elections officials will be ready. By their nature, she says, they're extremely capable of handling whatever crisis they may face.

And CISA has been doing its part to help them. Since the beginning of the current election cycle, Easterly says her agency has conducted hundreds of physical and cybersecurity assessments, table-top exercises, and training events with state and local officials -- all with the goal of reducing the risks posed by any kind of potential attack.

If anyone still has concerns about election security, Easterly encouraged them to reach out to their local elections officials for more information, or better yet, sign up to be a poll worker and get a first-hand look at the process.

And if what you're hearing about an election doesn't match up with what your local election officials tell you, "then it's probably just noise" she said.