Last week was a sobering one for Congress.

The second impeachment trial of Donald Trump served as the backdrop, the vivid videos of the angry mob of Jan. 6 underscoring all that could have been lost that day, and all that divides Americans.

In the House committee rooms, meanwhile, lawmakers worked on a giant economic relief package as we head into the second year of a deadly, isolating, growth-killing pandemic.

And finally, in a room far from the central action of the week, a handful of government and private-sector professionals held forth before the House Homeland Security panel on one harder-to-define but no-less-real challenge to this democratic republic. The shorthand word for it is cybersecurity — but that term trivializes the issue, and the challenge.

Cyber makes it sound like it belongs only to the province of the computer savvy, the geeks, as if it is some secondary technical problem that has a permanent fix.

It is not. This is an issue of national security, and of national survival, these intelligence and technology professionals said. The growth of the internet worldwide combined with the power of mass online messaging through social media, and available-to-all hacking tools, means that the United States is under constant, unrelenting attack from adversaries, foreign and domestic.

The attacks do not cease, will not cease and will be a permanent problem, like human disease, about which Americans have to be constantly vigilant, and which may never be eradicated.

This is not about just computer systems going down or getting glitchy. A public water supply was attacked earlier this month in Florida, which if it had not been foiled quickly could have sickened tens of thousands of people. The recent and ongoing SolarWinds hack, by Russian intelligence operatives, will be with us for years and is still only partially understood. It affects and will affect hundreds of top U.S. companies and many agencies of the federal government.

The attack on Congress of Jan. 6 was also borne of this technology revolution. It was aided and abetted by not only Trump's constant use of social media and television to tell a lie but by algorithms and actors, some shadowy and online, others elected and prominent, who promoted the same lie to the point of inciting a riot.

Meanwhile, identities are stolen, credit card accounts corrupted, small businesses paralyzed. Universities and school systems and local government computers are hacked and made to pay huge ransom payments to get unhacked, or take the hit and expense of weeks of rebuilding computer systems.

Christopher Krebs, the former head of the Cybersecurity and Infrastructure Security Agency, who was fired by Trump last year, told the House Homeland Security Committee that the use of ransomware now is a "scourge."

"I think we're on the verge of a global emergency," Krebs said of ransomware at the Feb. 10 hearing. "The rate at which we are seeing state and local governments get hit is truly frightening."

Sue Gordon, a former deputy director of national intelligence, told the committee that criminal hacking, by crooks and nation states, is "a global commodity now, everyone can cause harm. Formerly just the province of great powers, now it is available to anyone. … In a digitally connected world, one need not travel great physical distance or expend great resources to achieve malign outcome."

Disinformation also needs to be seen through the cybersecurity lens, according to the experts.

"We haven't talked much about disinformation as a part of the cyber threat, but it surely is, and we have learned it," Gordon said. "Disinformation is incredibly powerful, the ability to overwhelm airwaves with any sort of messaging."

Russia is the best practitioner of these dark technology arts, all of the professionals said at the hearing, but China, Iran and North Korea are learning fast.

And they have a clear objective. Said Gordon: "We know that our adversaries, particularly Russia but not exclusively Russia, have as their strategic imperative to undermine democracy."

Jan. 6 played right into their hands, Gordon said. Russian leaders will amplify the message of American division and hold up the images of violence at the U.S. Capitol globally to suggest that what Americans have professed about themselves is not true and that what Russia has at home is better and more stable.

In their Feb. 10 remarks, the experts echoed the October 2019 bipartisan report of the Senate Intelligence Committee on Russia's use of social media in the 2016 elections.

"Russian information warfare on social media is often aimed squarely at attacking a society and its relationship to its own democratic institutions," the report said. And one of those institutions is a free press.

"Information warfare, at its core, is a struggle over information and truth. A free and open press — a defining attribute of democratic society — is a principal strategic target for Russian disinformation," the senators concluded.

Jakub Kalensky, a former official with the European Union's rapid response team created to counter Russian disinformation, was quoted by the senators as saying, "It's not the purpose to persuade someone with one version of events. The goal for Russia is to achieve a state in which the average media consumer says, 'There are too many versions of events, and I'll never know the truth.'"

In the end, at the Feb. 10 hearing, despite the doom and gloom, the professionals at the Homeland Security Committee meeting were remarkably optimistic for the long term. Why? Because the tools and practices of democracies — openness, collaboration, sharing of information, a free media, working with allies — are the things that defeat mass propaganda, violence and division.

"We need to bring the problem into the light ruthlessly, because evil can't survive there. … Security and trust disproportionately favor the good guys, and we need to press our advantage," Gordon said.

Amen.

Patrick B. Pexton is CQ Roll Call's technology editor.