Top U.S. defense officials insist they are not turning a blind eye to fears that Russian hackers are trying to hijack upcoming U.S. presidential and local elections.
Still, the scope of the threat and just how the U.S. plans to respond remain unclear.
“This continues to be an issue of great focus,” said Adm. Michael Rogers, who serves as both National Security Agency Director and chief of the Defense Department’s Cyber Command.
“I’m not going to characterize this activity,” Rogers told members of the Senate Armed Services Committee on Tuesday, but added “I think there are scenarios where you could see capability applied.”
The question was first raised by Senate Armed Services Committee Chairman John McCain, a long-time Republican senator from Arizona who is running for reelection.
FILE - Adm. Michael Rogers, National Security Agency Director and chief of the Defense Department’s Cyber Command, testifies on Capitol Hill in Washington, Feb. 9, 2016.
“Russia is using cyber to undermine American national interest, and now it appears our democracy could be the next target,” McCain warned. “If you attack that and succeed in destroying that, you’ve destroyed democracy.”
U.S. defense, intelligence and law enforcement officials have long been worried about Moscow’s aggressive use of cyberspace for disruption and for intelligence gathering.
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On 'high alert'
The FBI and the Department of Homeland Security are currently investigating allegations Russian-linked operatives hacked into the email system of the Democratic National Committee. And the FBI has also told election officials in Arizona and Illinois that each state’s voter registration database may have been infiltrated, possibly by Russian agents.
“We are on all high alert,” Louisiana’s Secretary of State Tom Schedler told members of the House of Representatives during a separate hearing Tuesday.
But Schedler cautioned there is only so much hackers working at the behest of Russia or anyone else can accomplish, especially since voting machines are not connected to the internet.
FILE - People line up to vote inside a precinct in Matthews, North Carolina, March 15, 2016.
“Voter fraud is much, much harder to accomplish than you may think,” Schedler said. “While it would certainly be disruptive to have registration systems hacked as we saw in Arizona and Illinois, voters could still vote, and election day would still occur.”
Still, there are fears that manipulation of the voter registration rolls could cause problems.
“They need not attack every county in every state,” said Rice University Professor Dan Wallach. “It’s sufficient for them to go after battleground states where a small nudge can have a large impact.”
The result of a hack like that, Wallach warned, could temporarily knock people off voter rolls or cause more simple problems such as long lines. Still, he said it could create enough obstacles to disenfranchise voters.
Is there a policy?
“These are activities the government is taking quite seriously,” Defense Undersecretary for Intelligence Marcell Lettre told lawmakers.
Still, McCain and other lawmakers accuse the Obama administration of not doing enough.
“Do we have a policy as to how to respond to this interference?” McCain asked during a tense exchange with Lettre.
When Lettre began to refer to the ongoing investigations, McCain cut him off.
"I'm asking if we have a policy, and the answer is no," McCain said.
Despite the concerns, the NSA’s Rogers said any actor trying to hack the U.S. election system would face significant challenges.
"One advantage I do see from a defensive standpoint is that the structure is so disparate with some elements being still manually focused," Rogers said. “Because it’s not just one nationwide, single integrated structure, that tends to help us.”
“But is it a concern,” McCain asked.
“Oh, yes, sir,” Rogers replied.
VOA Science and Technology Correspondent Steve Baragona contributed to this report.