The fifth generation of wireless technology has the potential to upend the way cities work, but it'll all be for naught if 5G networks can't be properly secured, James L. Jones, a former U.S. national security adviser, said Thursday.

"I think we're involved in a very serious race that'll affect who we are as a nation for the rest of the century," Jones, a retired Marine general and former NATO supreme allied commander who served as President Barack Obama's first national security adviser, said at a smart-cities conferencehosted by the law firm Dentons. "4G" — the current wireless standard — "was a revolutionary technology that enabled things like smartphones and GPS, but 5G is disruptive."

But the new networks will only be as strong as their cybersecurity, Jones said.

"For all the good things we might think about in smart cities, there will be threats we have to deal with," he said. "We have to win, because our ability to win will affect data and security."