WASHINGTON (AP) -- The nation's cybersecurity agency has played a critical role in helping states shore up the defenses of their voting systems, but its election mission appears uncertain amid sustained criticism from Republicans and key figures in the Trump administration.

President Donald Trump has yet to name anyone to lead the U.S. Cybersecurity and Infrastructure Security, and for the first time since it was formed, there are no plans for anyone in its leadership to address the annual gathering of the nation's secretaries of state, which begins Thursday in Washington.

Trump's new homeland security secretary, Kristi Noem, said during her confirmation hearing that the agency had strayed "far off mission." She pledged to work with senators "should you wish to rein them in" with legislation.

The agency, commonly known as CISA, was formed in 2018 during the first Trump administration and is charged with protecting the nation's critical infrastructure, from dams and nuclear power plants to banks and voting systems. While it's under the Department of Homeland Security, CISA is a separate agency with its own Senate-confirmed director.

The agency has received bipartisan praise from many state and local election officials, but Trump and his allies remain angry over its efforts to counter misinformation about the 2020 presidential election and the coronavirus pandemic. The agency's first director, Chris Krebs, was fired by Trump after Krebs highlighted a statement issued by a group of election officials that called the 2020 election the "most secure in American history."

That drew Trump's ire as he was contesting his loss to Democrat Joe Biden. Republicans have claimed repeatedly since then that CISA had worked with social media companies to censor conservative viewpoints on issues related to elections and health.

Agency officials have disputed that: "CISA does not censor, has never censored," the agency's then-director, Jen Easterly, said last fall in an interview with The Associated Press. Nevertheless, Republicans continue to blame the agency and insist changes are necessary.

"Joe Biden's Cybersecurity and Infrastructure Security Agency (CISA) was more focused on undermining President Trump than they were protecting our own critical infrastructure," Rep. Marjorie Taylor Greene, a Trump ally from Georgia and chair of the newly formed House subcommittee on Delivering on Government Efficiency, said in a social media post last week. "The thugs responsible for that kind of waste and abuse will be held accountable!"

During the 2020 election, agency officials worked with states to help them notify social media companies about misinformation spreading on their platforms, but they have said they never instructed or sought to coerce those companies to act. For the 2024 election, CISA and other federal agencies alerted the public to various foreign misinformation campaigns, including a fake video linked to Russia purporting to show the mishandling of ballots in Pennsylvania.

In recent months, Meta CEO Mark Zuckerberg has echoed the GOP claims and announced plans to dismantle the company's fact-checking program.

One of the first actions Trump took after returning to the White House on Jan. 20 was a signing of an executive order "ending federal censorship" and instructing his attorney general to investigate federal actions under the previous administration and to propose "remedial actions." There is little information about what's next and whether CISA's mission could change under new leadership.

Project 2025, a conservative blueprint for a Republican administration, recommended that CISA be moved to the Transportation Department and focused solely on protecting government networks and coordinating the security of critical infrastructure.

It said the agency should only help states assess whether they have "good cyber hygiene in their hardware and software in preparation for an election -- nothing more." That's what the agency has been doing in recent years, by providing training and security reviews.

Voting systems were designated critical infrastructure after an effort by Russia in 2016 to interfere in that year's presidential election, which included scanning state voter registration databases for vulnerabilities.

Some state election officials were initially resistant to the idea of federal assistance. But many now credit the agency and federal money with helping them improve security ahead of the 2020 and 2024 presidential elections.

"There were quite a few of us secretaries who were skeptical that the federal government was trying to take over the conduct of elections, and I was one of them," said Kim Wyman, Washington state's former secretary of state who later served in a leadership role at CISA. "It became a partnership, and our systems were stronger because of it."