The Navy has just released its plan for robotic unmanned surface vessels These look like vehicles that can greatly enhance the flexibility of navy operations and help ensure greater control of the surface and subsurface area around larger manned navy vessels.
All four classes of unmanned surface vessels
Table of missions
Smallest X class USV for recon mainly
Harbor class specifications, 7 meters long, Zodiacs with weapons, can defend against attacks like the one on the USS Cole
Snorkler class, 7 meter submarine, stay in the water for 1 day
Fleet class USV, 11 meters long, good speed and able to stay in the water for 2 days
If costs were held down to $1 to 5 million per USV and UAV, then it would make sense to spend 10%-50% of the Navy budget to provide 10-100 USVs and UAVs per manned Navy Vessel. Every manned ship would have the equivalent of an unmanned carrier group. Mini-unmanned carrier groups would be far cheaper than current manned versions.
This is the damage to the USS Cole. A Zodiac with a couple of terrorists and explosives was allowed to get too close to the USS Cole. Robotic Zodiacs could intercept and challenge such craft at a standoff distance from Navy vessels.