The recent emergence of 3D printing as an alternate
manufacturing technology could change how states evaluate the cost of
embarking on or (in the case of North Korea) accelerating missile development
programs. 3D printing has the potential
to greatly reduce the costs and expertise requirements of these and other
proliferation programs. Employed strategically, 3D printing could reduce cycle
times in development of missiles and other military systems – and with the
right printers and software – even reduce the number of skilled engineers
needed for such programs.
So what exactly is 3D printing and how does it compare with
traditional manufacturing methods? 3D printing is also described as “additive
manufacturing” whereas use of traditional CNC machine tools is considered
“subtractive manufacturing.” Whereas CNCs cut and shape an object from a
larger piece of material, additive manufacturing equipment builds a
three-dimensional object layer-by-layer through the heating of metal powders or
plastic resins into solid forms. The 3D
object is, in effect, “printed.” Similar
to their CNC-based subtractive manufacturing cousins, 3D printers are
computer-controlled with the precise shape of the “printed” object determined
by a design file used with the printer’s software.
Because 3D printers can produce a wide variety of
three-dimensional metal or plastic objects, the potential commercial and
industrial applications are vast, generating much buzz about the arrival of a
new manufacturing revolution. Motivated by the potential cost and technical advantages, the U.S. National Aeronautics and Space Administration (NASA) and aerospace manufacturer Space-X are already experimenting with 3D printing in the manufacture of rocket engines.  The U.S. and British Navies have been using 3D printers on aircraft carriers at sea to produce customized drones during deployments.  The revolutionary implications for nonproliferation of this new manufacturing method warrant closer consideration.
Matthew Kroenig and Tristan
Volpe assessed the nuclear nonproliferation dimension of this development with
their article titled “3D printing the bomb?” and the topic is garnering attention
among policy analysts.  Much of the concern surrounds whether 3D
printing represents a new way for a state-level WMD program to circumvent
nonproliferation export controls by offering a convenient way to produce
sensitive (export controlled) components. As the Nuclear Suppliers Group and Missile Technology Control Regime
developed their guidelines in an era when subtractive manufacturing was
dominant, few export controls are in place specifically focused on 3D
printers. However, traditional export
controls can still apply to the inputs (design file and some metal powders) and
outputs (printed object) of 3D printers.
The increased availability of home-use 3D printers complicates efforts to manage the proliferation risk posed by additive manufacturing. This development converges with the ongoing growth of e-commerce marketplaces and “one-click” shipping, meaning that individual online sellers are now able to manufacture their own goods as well as sell them. Of course, the capabilities of home-use 3D printers are far
from the industrial-scale additive manufacturing equipment employed by the
Lockheeds, Raytheons, and GEs of the world. However, the emergence of “makerspaces” –where 3D printers and other
manufacturing equipment in a central workspace can be shared via a co-op type
arrangement – may bring advanced production capabilities to a neighborhood near you. Even if a “makerspace” is not close by, a
design file can be sent electronically to a 3D printing services company – or
perhaps the customer’s own location if he/she has a suitable 3D printer on
site. The production and
sale of sensitive WMD-relevant dual-use goods by these new modes is not
entirely hypothetical. Researchers at
King’s College London and the Center for Nonproliferation Studies have
identified export-controlled dual-use goods such as pressure transducers and freeze
dryers for sale on e-commerce sites such as Alibaba.  As illustrated by University of California at
San Diego students’
launching of a rocket with a fully 3D-printed engine, truly
widespread “garage”-based production of rockets and other export controlled
items may not be far away either. 
emerging scenario will require creative thinking and solutions on the part of the
nonproliferation community – and in a way that does not stifle the genuine
benefits 3D printing offers for economic and human welfare. Traditional export controls will still be
essential, but they will have to be supplemented by nonproliferation
awareness-building beyond outreach to traditional industrial actors. Moreover, the transmissibility of 3D printing
design files will demand similar attention in the cyber-security domain. Otherwise, states such as North Korea will
be well-positioned to tap into the 3D printing revolution, learn from it, and
incorporate it into their missile production capabilities. Well-resourced terrorist organizations and arms
traffickers also may be tempted to exploit 3D printing for weapons production,
and, just as legitimate commercial traders at the factory/warehouse level have
been joined by new entrepreneurs at the garage/living room level, proliferators’
ranks may also be augmented by new illicit supply chains supporting them.
 “South Korea retrieves North Korean Unha-3 Rocket debris,” Spaceflight101.net, December 15, 2012.
 “Report of the Panel of Experts established pursuant to resolution 1874 (2009), United Nations Security Council, Sanctions Committee (1718), Panel of Experts Report, S/2014/147 – pp. 22-24.
 Jeffrey Lewis and Amber Lee, “Happiness is a Warm CNC Machine Tool,” 38 North, September 4, 2013 (accessed on 1/22/2017)
Newton, “NASA Engineers Test Combustion Chamber to Advance 3-D Printed Rocket
Engine Design,” NASA.gov, December 8, 2016.
Kyle Mizokami, “The future of America’s aircraft carriers? Floating drone factories,” The Week, April
21, 2016; Jon Rosamond, “U.S., U.K. Navies Expanding Experiments Using 3D
Printing,’ USNI News, September 22, 2015.
 See Matthew Kroenig and Tristan Volpe, “3D Printing the Bomb? The Nuclear Nonproliferation Challenge,” The Washington Quarterly, Vol. 38, No. 3, Fall 2015, pp. 7-19; for a rebuttal to Kroenig and Volpe’s piece, see Amy J. Nelson, “The Truth About 3-D Printing and Nuclear Proliferation,” War on the Rocks.com, December 14, 2015; for another influential work (particularly in the export control domain) on 3D printing and contemporaneous with Kroenig and Volpe’s piece, see Grant Christopher, “3D Printing: A Challenge to Nuclear Export Controls,” Strategic Trade Review, Vol. 1, No. 1, Autumn 2015, pp. 18-25.
Charles Clover, “Alibaba: Weapons of mass ecommerce,” The Financial Times,
September 26, 2014; Raymond A. Zilinskas and Philippe Mauger, “Biotechnology
E-commerce: A Disruptive Challenge to Biological Arms Control,” CNS Occasional
Paper No. 21, James Martin Center for Nonproliferation Studies, Middlebury
Institute of International Studies at Monterey, nonproliferation.org
Kelsey D. Atherton, “University Students Launched a Rocket with Completely
3D-printed Engine,” Popular Science,
May 25, 2016.