SIMI VALLEY, Calif. — The Air Force will propose spending $9 billion over the next five years to build a system to automatically send intelligence to front-line forces, new technology that strategists say will change how the military fights and will help deter aggression by Russia and China.

The new system, officials say, aims to end what has become an increasing vulnerability: The speed of the military’s communications system hardly matches the speed of modern warfare.

Much of the Air Force’s fleet of aircraft was developed and built decades ago, and few planes can pass data between them automatically. Instead, information is collected by a satellite camera, drone feed or fighter plane radar and sent back to a command center where human analysts look at the information and push it out to pilots, ship captains or ground commanders.

“In the speed of war that we are talking about, denying an invasion by Russia of the Baltics, denying an invasion of Taiwan, you will never be able to fight at the speed you need to if you are talking on a radio,” said Brig. Gen. S. Clinton Hinote, a senior Air Force official. “You have to do it faster.”