The U.S. can then use the embedded codes to launch attacks at will against a nation's critical infrastructure, according to Richard Clarke, who served 11 years in White House national security policy roles.
"You can't just wake up one day and decide you want to hack your way into an opponent's power grid. The U.S. has to do that months or years in advance," Clarke said. "You have to embed now because the enemy is constantly changing firewalls and installing new intrusion devices. You want to be inside the network and leave a trap door so that you can get back inside at all times."
Clarke says a half a dozen other countries are also engaging in the cyber-espionage by getting into the networks of their opponents every day without ever being detected.
He says the most developed and most dangerous threat to America is from China, which manufactures computer parts used in laptops and network computers around the world.
The National Security Agency (NSA) constantly probes the nation's networks for vulnerabilities.
Last month, Congress confirmed NSA Director General Keith Alexander to lead the new Cyber-Command. That new military command will play a defensive and offensive role to protect the intelligence department and the military.
No one in the government has the mission to actively defend the dot-com private domain.
Because of that, Clarke says millions of gigabytes of data are stolen every day.
"It happens to companies all the time and they don't ever know it. It's literally libraries of Congress, many libraries of Congress worth of information, gone in minutes," Clarke said.
Cyber-security experts at a counter-terrorism forum at the Aspen Institute this week debated who and how to best protect the private sector in cyberspace and whether an international cyber-arms agreement is needed to help protect data.
The Homeland Security experts agreed it will take all Americans to successfully fight every kind of terrorism in America, be it cyber, biological, chemical or nuclear.
"It's not a matter of scaring people but letting them know the threats are real," Frances Townsend, former chair of the Homeland Security Council, said. "You don't want Americans running around frightened about the next attack because that's not effective. But you have to prepare them for what's inevitable."
Investigative Reporter Deborah Sherman is attending a Counterterrorism Forum in Aspen. If you have any questions for homeland officials, please e-mail Deborah.Sherman@9NEWS.com.
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