Just how big a threat are cyberattacks to US security?

Government agencies and private companies are beginning to work together to ensure that foreign nations and extremists are unable to steal intellectual property or invade critical American infrastructure.

Ten years ago, if you asked U.S. security officials what the greatest external threat to the country was, they'd probably tell you it was the possibility of a well-trained and well-funded foreign extremist group carrying out a catastrophic attack on U.S. soil.

Today, while domestic and foreign terrorists remain a peril, the defense landscape has changed.

On Tuesday, President Barack Obama signaled that shift, signing an executive order that gives government agencies more resources to share information with each other and with private corporations, as well as the ability to establish a framework that protects the nation against cyberintrusions.

The president, as well as members of his cabinet and Congress, including outgoing Secretary of Defense Leon Panetta, have long called for more attention to be paid to America's cyber weaknesses. They stressed just how calamitous it would be if a terrorist group were to gain entry into a city's power grid or water supply, or if a foreign nation were able to sneak into a major American bank's computer system. 

The cyberthreat isn’t just a hypothetical risk. Intrusions and theft already are happening. Foreign nations are slinking into the technological infrastructure of government agencies and private corporations and stealing hundreds of millions of dollars worth of intellectual property.

According to McAfee Inc., the global cost of cybercrime has reached $1 trillion. Symantec estimates that cybertheft costs American companies $250 billion per year.

"The magnitude, severity and persistence of threats is finally becoming apparent and appreciated by decision-makers at every level of government," Joseph V. DeMarco, a partner at the technology law firm DeVore & DeMarco, told MSN News.

"It can't be ignored anymore, and it can't be solved by simple technology," DeMarco said. "It's a perfect storm which requires a serious, integrated response.

DeMarco points to the proliferation of e-commerce as evidence of American technological susceptibility. Millions of companies are online, with consumer information available for the taking if it is not properly protected.

The integration DeMarco refers to — and President Obama has called for — is a partnership between the public and private sectors to make sure they're doing everything in their power to protect vital computer systems and share information about cyberthreats. Cooperation is tricky, however.

While lawmakers across the board understand the severity of the cyberthreat, they have yet to fully agree on how it should be dealt with. A bill to extend cybersecurity into the private sector was rejected last year by Senate Republicans who felt it would be financially burdensome on American companies.

Robert Rodriguez, a former Secret Service agent and chairman of the Security Innovation Network, which advances collaboration between the public and private sectors to defeat cyberthreats, warns that lawmakers are walking a tightrope with cybersecurity legislation. While he agrees there's a clear and present need for a solution, he believes reactionary government mandates won’t solve the problem. Instead, he argues, public-private partnerships are what federal agencies need to foster and learn from before they rush to enact legislation. Rodriguez himself has worked with the federal government (the departments of which he asked to keep private) and private security firms to facilitate the transfer of information between the two sectors.

Despite his concerns about the idea of federal regulation, Rodriguez says he understands the urgency of the crisis at hand, and that it warrants Congress’ attention. If the government pushes forward with collaborative law-making, he believes initial cybersecurity legislation — while imperfect — will form a solid foundation for a more effective bill to come later on.

"It's time to plant a stake in the ground — to own it, lead it and amend it. It won't be perfect, but we don’t have time to wait for perfection," he told MSN News.

With or without federally-mandated regulations, cybersecurity experts say market trends and palpable dangers are causing businesses to pre-empt further attacks by improving their defenses. DeMarco says businesses — many of which rely on an immense online presence with e-commerce and digitized information — are beginning to demand more accountability from each other. Together, he says, companies are ushering in an important era of information sharing, even if Americans aren't hearing about it every day.

"Companies interact with each other and share data and ask the right questions," he says. "Solutions that are market-driven are ultimately more effective than top-down government mandates.

"My hope is that these interactions — which never make pressrooms — continue."

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