Donald Trump. REUTERS/Kevin Lamarque

Eight out of the 28 members on the White House's National Infrastructure Advisory Council, which is responsible for overseeing the US' response to emerging cyber threats, resigned last week.

The letter that advisers — many of whom were Obama-era appointees — submitted to the White House was published by Nextgov and cited several reasons for leaving, including President Donald Trump's controversial response to the riots in Charlottesville that were sparked by white supremacists; Trump's decision to withdraw from the landmark Paris climate deal; and his "insufficient attention" to possible cyber threats posed to American infrastructure, including its election systems.

Trump's actions, the letter said, "have threatened the security of the homeland I took an oath to protect." It added that the administration's actions "undermine" the "moral infrastructure of our Nation" which "is the foundation on which our physical infrastructure is built."

Though Trump has at times spoken about addressing "the cyber," he has been reluctant to address perhaps the most pressing cybersecurity threat the US currently faces: Russia.

Historically, the US "has been inadequate" when it comes to addressing potentially devastating cyberattacks from a nation state like Russia, said Carbon Black national-security strategist and former FBI counterterrorism operative Eric O'Neill. "This inadequacy has carried over into the current administration, where our president's understanding of technology is limited to Twitter," he added.

Former FBI Director James Comey confirmed in a hearing before the Senate Intelligence Committee in March that the bureau was investigating Russia’s interference in the 2016 election, which the US intelligence community concluded was done in an effort to tilt the election in Trump's favor. Russia's meddling was multi-faceted and included cyberwarfare tactics like hacking the Democratic National Committee email servers and giving the material to WikiLeaks, as well as breaching US voting systems in an effort to steal registration data that officials say could be used to target and manipulate voters in future elections.

After gaining access to the DNC’s system in 2016, Russian hacking groups Fancy Bear and Cozy Bear disseminated thousands of emails via hacker Guccifer 2.0, who leaked the information to WikiLeaks. Cybersecurity experts at the intelligence firm ThreatConnect linked Guccifer 2.0 back to Russia and concluded the hacker was the product of a Russian disinformation campaign.

The US intelligence community “is confident that the Russian Government directed the recent compromises of e-mails from US persons and institutions, including from US political organizations,” then-Director of National Intelligence James Clapper and the Department of Homeland Security said in a joint statement shortly after the first batch of emails from the account of John Podesta, Hillary Clinton's campaign manager, were first leaked last year.

Hillary Clinton at her concession speech in New York. Justin Sullivan/Getty Images

In addition to hacking the DNC, Bloomberg reported in June that Russian hackers attacked election systems in as many as 39 states, though voting tallies are not believed to have been altered or manipulated in any way.

The report was bolstered by a leaked NSA document published by The Intercept earlier that month detailing how hackers connected to Russian military intelligence had attempted to breach US voting systems days before the election. National-security experts were floored by the document and said it was the clearest evidence so far that Russia interfered in the election.

If Russia launches another cyberattack on the US, as the intelligence community believes it will, critical infrastructure like power grids, water supplies, and communication systems "will likely be the first on the list for our enemies to attack in an event of war," O'Neill said.

To be sure, Russia has increasingly emerged as a central figure following a slew of high-profile cyberattacks across the globe over the past few years. In addition to interfering in the US election, Russia is thought to be the culprit behind an elaborate effort to turn Ukraine into a cyber-weapon testing ground.

Officials also believe Russia may have been behind the "Petya" cyberattack that crippled countries and corporations across the globe.

Investigators have additionally linked Russia to attacks on at least a dozen US nuclear facilities. The hacks, though confined to the enterprise side of the nuclear plants, raised red flags as they could be a preliminary step toward an attack against the US power grid.

Despite the growing threat Russia poses to the US, Trump and Russian President Vladimir Putin discussed the development of a joint US-Russia coalition tasked with combatting cyber threats and boosting cybersecurity after last month's G-20 summit.

Experts were baffled by the "bizarre" proposal and said that by agreeing to a US-Russia cybersecurity task force, Trump was implicating the US in Russia's propaganda and disinformation campaign.

Following swift backlash against the idea, Trump said he would not pursue the coalition with Russia.

Given Trump's apparently limited understanding of the rising threat of information and cyber-warfare, O'Neill said it was "unfortunate" that a quarter of the members on the NIAC resigned, adding that now that they've left the council, "they simply don't have a voice," whereas before, "they could have worked together to close security gaps."