Mike McCaul: Sony Hack Shows Need for Rules on Cyberwarfare

The cyberattack on Sony Pictures reveals the need for clearer rules on cyberwarfare, Rep. Mike McCaul says.

"It's kind of a new frontier," the Texas Republican said Thursday on CNN's "The Lead with Jake Tapper."

McCaul noted that Iran has hit America's financial sector, and Russia and China also have hacked into corporate and government computers.

"We need to calculate what is an act of warfare in cyberspace, and what is the appropriate response and retaliation in the event of an act of cyberwarfare," McCaul said. "I don't think that's clearly defined right now."

White House spokesman Josh Earnest said Thursday the United States would have a "proportional response" to the attack on Sony Pictures and threats of terrorism against any theaters showing "The Interview," a comedy about the assassination of North Korean dictator Kim Jong-un.

The FBI has tied the cyberattack to the North Korean government.

Sony Pictures has pulled the film from release, an act that McCaul and other politicians have said is caving to a terrorist threat.

Rep. Ed Royce of California told CNN's "The Situation Room with Wolf Blitzer," that it is harder to retaliate in-kind since North Korea essentially has no banking infrastructure or private sector economy.

"Frankly, there's only two areas where they put all of their capital," Royce said, their nuclear weapons program and cyberwarfare.

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