SAN DIEGO – The wave of automation that swept away tens of thousands of U.S. manufacturing and office jobs during the past two decades is now washing over the armed forces, putting both rear-echelon and front-line positions in jeopardy.

"Just as in the civilian economy, automation will likely have a big impact on military organizations in logistics and manufacturing," said Michael Horowitz, a University of Pennsylvania professor and one of the globe's foremost experts on weaponized robots.

"The U.S. military is very likely to pursue forms of automation that reduce 'back-office' costs over time, as well as remove soldiers from noncombat deployments where they might face risk from adversaries on fluid battlefields, such as in transportation."

Driverless vehicles poised to take taxi, train and truck driver jobs in the civilian sector also could nab many combat-support slots in the Army.

Warehouse robots that scoot goods to delivery vans could run the same chores inside Air Force ordnance and supply units.

New machines that can scan, collate and analyze hundreds of thousands of pages of legal documents in a day might outperform Navy legal researchers.

Nurses, physicians and corpsmen could face competition from computers designed to diagnose diseases and assist in the operating room.

Frogmen might no longer need to rip out sea mines by hand — robots could do that for them.

"Robots will continue to replace the dirty, dull and dangerous jobs, and this will affect typically more uneducated and unskilled workers," said Henrik Christensen, director of the Institute for Contextual Robotics at the University of California, San Diego. "You need to look at the mundane things. Logistics tasks will not be solved by people driving around in trucks. Instead, you will have fewer drivers. The lead driver in a convoy might be human, but every truck following behind will not be. The jobs that are the most boring will be the ones that get replaced because they're the easiest to automate."

As for warships, Horowitz said because of economic and personnel reasons, they're increasingly designed to "reduce the number of sailors required for operations."

The highly automated guided-missile destroyer Zumwalt that arrived in San Diego in December carries 147 sailors — half the crew that runs similar warships — and deploys as many as three drone MQ-8 Fire Scout helicopters to find targets, map terrain and sniff out bad weather.

The Office of Naval Research and the Pentagon's Strategic Capabilities Office continue to experiment with what futurists call a "ghost fleet" of unmanned but networked surface and underwater boats — and their flying drone cousins overhead.