He told the committee the world is moving fast ... But laws and policies in America are not keeping up.
He also said if terrorists are able to launch cyber attacks against U.S. cities or the U.S. military ... there could be devastating consequences.
"Our military is more dependent upon cyberspace than any military in the world. And as a matter of fact, we're at the point where we would have a hard time operating as a military if the use of cyberspace were denied to us. And our adversaries know that, so they're looking for vulnerabilities. And it is a potential vulnerability that we've got to pay a lot of attention to."
Representative Thornberry said terrorists could use cyber attacks to give viruses to unmaned aerial vehicles, or to disrupt electric grids, water plants, or worse.
He said lives could be lost if terrorists launched severe cyber attacks.
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