The US military increasingly relies on drones to carry out a
multitude of tasks, usually those deemed too “dull, dirty, or dangerous”
for manned missions. Most unmanned aerial vehicles (UAVs) carry out
routine reconnaissance. They also act as decoys, serve as communication
relays, and even deliver light cargoes. But a growing number of drones
are armed, such as the US Predator and MQ-9 Reaper, which are used
mostly in tactical situations, such as targeting terrorists or
insurgents.
Now military strategists are considering acquiring longer-range
drones, especially those capable of carrying out nuclear missions. In
2015 there were reports that Russia was attempting to build
nuclear-armed drone submarines.
It is a controversial strategy, given that it takes all the usual
qualms there are about the increasing use of autonomous systems for
war-fighting – the ethics of devolving too much authority to what are
basically robots, susceptibility to hacking, etc. – but with much
greater destructive power, given these systems’ range and payload.
Nevertheless, it is at least worth considering.
In fact, such a strategic drone may already be in the offing. When
the US decided to go ahead with a next-generation strategic bomber, the
Long-Range Strike Bomber (LRS-B), the program included both manned and
unmanned systems. The LRS-B, or B-21 Raider, which replaces both B-52
and B-1 bombers, is intended to carry out a broad range of missions:
nuclear attack, strategic and tactical conventional strike,
surveillance, intelligence, and reconnaissance (ISR), and electronic
attack. Initially, the US military plans to acquire 80 to 100 LRS-Bs,
but the number could eventually rise to 200 bombers.
Some of these missions probably do not require a manned system, and
thus a drone version of the LRS-B could perform many of the more mundane
tasks, such as ISR or electronic attack, without putting unnecessary
stress on crews.
Conventional strike missions with precision-guided air-to-ground
munitions is also something that could be considered for an unmanned
system, as it would provide the US with the means for long-range,
large-payload ground attacks. These types of missions can presently be
carried out only by B-52 and B-1 bombers, which are becoming
increasingly obsolete; shorter-range systems such as the F-35 Joint
Strike Fighter, area very limited in their capacities for ground attack.
In such a role, an unmanned LRS-B could probably pack quite a lethal load and avoid putting a manned crew in harm’s way.
More controversial, perhaps, is the idea of an unmanned version of
the LRS-B delivering nuclear weapons. Of course, the US military already
operates a number of unmanned nuclear-delivery systems; they are called
ballistic missiles (think of them as a single-mission, one-way drone).
Nevertheless, nuclear-armed drones still raise considerable hackles.
What if such a drone could be hacked and forced to crash or be
redirected to another target? How does the drone’s remote operator
ensure near-total control of such a lethal weapons platform?
And nuclear drones could come in smaller packages, too. Thus far
there have been limitations on the transportability by air of nuclear
bombs with relatively high yields.
One of the goals of a nuclear weapons designer is to achieve the
optimum yield-to-weight ratio – that is, the amount of bang per mass,
usually expressed in terms of kilotons per kilogram (kt/kg). And thus
far, we have needed powerful airplanes and missiles to deliver such
explosive capability (compared to conventional warheads) in such
relatively small amounts of weight compared to the amount of
conventional warheads we would need to achieve the same destructive
power.
But the technology of additive manufacturing may diminish this
problem. At least in theory. Additive manufacturing – where 3-D printing
machines can build objects of any shape and size by laying down
successive layers of material – brings new opportunities for building
much more lightweight structures.
A structure can be built with the needed strength but can be
considerably lighter than a conventionally-built counterpart. One
approach, for instance, is to build a lattice structure of different
chemical components – either for the delivery system or the bomb casing
itself, since the mass of plutonium or uranium itself cannot be
modified.
More lightweight nuclear weapons present new deployment and delivery
opportunities. They could be much more furtive and more difficult to
detect; they could be carried by small drones and therefore be much
harder to detect by enemy air defenses, since an adversary would
normally be expecting a ballistic or cruise missile, or a bomber.
Longer-range drones make a lot of sense for the US military, when it
comes to projecting power into the far Western Pacific. It still suffers
from the centuries-old challenge of the “tyranny of distance.” It can
take up to three weeks for US naval forces to steam from ports on the
west coast to the South China Sea. Forces based in Hawaii could take up
to 16 days to reach this area, and even Guam is a 3- to 5-day journey
away. Considering this strategic straightjacket, drones make a lot of
sense.
A nuclear-armed UAV may not be on the horizon any time soon, but it
is a certainty that longer-range armed drones are coming, and perhaps
sooner than we think. The promise of such a system, and the strike
options it offers, are going to be just too irresistible to pass up.
Especially for the US military, which is seeking so-called “third
offsets” capabilities in order to redress its growing vulnerability to
long-range strike by such potential adversaries like China, a strategic
drone would probably be quite appealing.
