Editor's Note: (Former U.S. Rep. Mike Rogers is the former chairman of the House Permanent Select Committee on Intelligence and the host of CNN's "Declassified" TV series airing Sundays at 10 p.m. ET/PT starting June 19. The views expressed in this commentary are his own.)
(CNN) Most American counterterrorism, espionage and counterintelligence operations, from the Cold War to the Iraq War, are unknown to the public at large.
But we know, implicitly, that the U.S. intelligence community, military and special operations forces work quietly in the shadows to keep America safe.
And today, espionage threats against the United States pose as great a threat as ever.
Hundreds of intelligence officers from foreign nations continue to pose as diplomats, journalists and businessmen, just as they have for hundreds of years.
Recent decades have seen the addition of other types of intelligence gathering: improved signals intelligence to spy on enemy communications, image intelligence that uses photography from space, and most recently what is commonly called cyberespionage, or using computers to monitor, sabotage or steal classified information online.
For too long the public largely ignored or misunderstood the threat posed by cyberespionage. High-profile breaches at the State Department and Officer of Personnel Management and efforts by hacking collectives, Eastern European and Asian criminals and even Hollywood have raised awareness of the general threat, which continues to spread as more Americans have their identities or credit card information stolen.
But unlike most traditional methods of intelligence, cyberespionage has become a multiheaded hydra, targeting more than just America's government and military.
In a more complex area, and one of graver importance, cyberespionage now endangers American companies' intellectual property.
This threat we see from China and Russia, in particular, threatens our soft underbelly: our private sector. Not long ago, security analysts estimated the global economic cost of cybercrime to be $445 billion.
Criminals, nation-states and nation-state-sponsored hackers have begun bleeding businesses of their extensively researched and developed products, simply replicating materials for a fraction of the cost and putting them back on the world market in direct competition with American goods.
And because the United States represents a free market economy that respects property rights, rather than one of gross cronyism, we are unable and unwilling to respond in kind.
Those same countries also use cyberespionage in more traditional ways: to steal government secrets and sniff out American spies, and identify America's Chinese or Russian assets. The Chinese have also been accused of hacking pro-democracy groups in Hong Kong to disrupt their activities and eavesdrop on their communications.
And in a technological twist on its authoritarian tendencies, the Russian intelligence services now use the Internet and satellite television for propaganda purposes, including to quell internal dissent and manipulate public dialogue in the United States and elsewhere.
Meanwhile, cyberespionage can occasionally work hand in glove with another central aspect of our changing intelligence landscape: cyberwarfare.
We saw in the Republic of Georgia in 2008 and in Ukraine in 2014 how Russian forces prepped the battlefield by causing power outages and shutting down government computer systems.
China has reportedly made the decision to boost its cyberwarfare capabilities by as much as 30% in a move designed to try to give it parity, if not an asymmetric edge over other major powers in that battle space.
Cybertheft, cyberespionage and cyberwarfare represent the Wild West of intelligence and direct action, with poorly delineated lines setting the three apart, and poorly formed internationally accepted norms guiding responses to the threats. With the ability to hide a hacking trail, use proxies in an attack or feed government-level technology to criminals, the attribution capability for such activity continues to be murky, with easy deniability for unsavory actors.
Recently, a fourth area of threatening cyberactivity has surfaced: nation-states using destructive hacking for political purposes. The Iranians who hacked the Las Vegas Sands Corp. and the North Koreans who attacked Sony Pictures crossed a new threshold by targeting private companies for punitive, rather than pecuniary, reasons.
No company, no matter how prepared, can withstand the determination and resources of a country.
And just this week, Russian hackers allegedly broke into the Democratic National Committee's servers and stole research on presumptive Republican presidential nominee Donald Trump.
As my new CNN Original Series "Declassified" will show, patriots work every day and night to protect American lives and assets from enemies all over the world. The cyber realm presents a new arena for their efforts, one that we have not yet quite mastered. With new frontiers of concern still unfolding, however, you can bet we will see the emergence of more intelligence activity in the cyber realm.
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