Long endurance aircraft….
5-20 MW is 6,700 to 26,800 hp. The upper end of this is about the power needed for a C-130. Using boosters for take-off, a very large aircraft could be design with range and endurance limited by its mechanical reliability and needed for crew food and water.
Large “Loitering” aircraft could serve as AWAC’s type sentries. An unmanned version, a “super predator” drone could be launched, travel across the world to it’s combat zone, then provide observation and fire missiles, until the ammo ran out or it was shot down.
And as transports, the FF power unit would allow non-stop flights around the world. This would have much more change effect on civilian rather then military usage, as the military already has mid-air refueling to allow this.
Fuel costs savings would be huge, all the way around.
One effect would be in balance of power. United States has mid-air refueling, other top tier military powers have it. But with FF powered aircraft, round the world flights would be possible with out the highly trained crews and world wide base structure the US has.
All in all, Focus Fusion would level the military playing field, putting more power in the hands of smaller or less economically powerful countries.