White Hulls Must Prepare for Gray Zone Challenges

By Lieutenant Commander Craig Allen Jr., U.S. Coast Guard

This question strikes closer to home for the Coast Guard than many may realize. The vessel the riverine craft were en route to rendezvous with when they were captured was the USCGC Monomoy (WPB-1326), one of six 110-foot Coast Guard patrol cutters forward deployed to the Arabian Gulf. The Monomoy (which had herself been in the international spotlight after an August 2014 altercation with an armed Iranian dhow 2 ) observed the incident from just outside Iranian territorial waters, relaying events to the Combined Task Group 56 Maritime Operations Center and other U.S. units in the area. If the riverine crews had chosen to resist capture, the Monomoy would have been the only U.S. unit near enough to provide assistance. The extent to which she and riverine units could have coordinated defensive efforts by employing common doctrine, tactics, and understanding of one another’s capabilities was not addressed in the Navy’s official investigation, but a closer look would not have found much to inspire confidence.

The riverine incident invited scrutiny into the preparation and operational employment of Navy littoral forces in the Arabian Gulf. It also should be a catalyst for the Coast Guard to critically examine the purpose, preparedness, and way ahead for its Bahrain-based patrol boat squadron and support staff, Coast Guard Patrol Forces Southwest Asia (PATFORSWA). 3 From a planning perspective, PATFORSWA offers insights that are especially relevant to defining the Coast Guard’s future role in complex, ambiguous, and volatile environments—the so-called gray zones.

Gray Zone Challenges

The value of deploying patrol and riverine craft to a region where the United States almost always maintains at least one carrier strike group may not be apparent without a closer look into the dynamics of the Arabian Gulf operating environment. While preponderant U.S. military power helps keep a lid on the latent hostility between Iran and its neighbors, an intense contest for influence rages on behind the scenes. Iran strives to blunt the U.S. and Gulf Cooperation Council (GCC) conventional military advantage and regional influence by employing proxy and irregular forces to, among other ends, discredit the U.S. narrative and foment Shia uprisings. Non-state actors such as terrorists, pirates, and smugglers are quick to exploit any gaps in maritime governance. Disputes over maritime boundaries and fishing rights contribute to the volatility. All pose threats to U.S. interests, yet these challenges are not ones that large surface combatants are well suited to confront. As a result, the United States maintains a sizable force of Navy and Coast Guard patrol craft and smaller vessels in the region to perform a variety of maritime security and cooperative engagement missions. 4

The diversity of maritime operations in the Arabian Gulf demonstrates the virtue of a balanced fleet that can respond to both high- and low-end challenges. For the United States, however, maintaining such a balance is becoming more difficult. Adversaries’ ever-improving capabilities have prompted a renewed focus on technical enablers and war­fighting skills. Secretary of Defense Ashton Carter recently issued a clear mandate for the Navy to prioritize high-end combat capability over a more balanced high-low mix. 5 Meanwhile, on the low end of the conflict spectrum, adversaries increasingly are finding ways to circumvent a traditional contest of naval strength by pursuing their objectives through indirect methods that avoid triggering a military response. Such an approach has many historical precedents and associated terms, such as irregular, hybrid, and asymmetric warfare. Recently, though, “gray zone challenges” has been widely used to describe the strategy’s impact on the modern operating environment.

Gray zones are receiving intense interest from the national security community because of the success with which adversaries have exploited them, revealing gaps in our ability to respond. A U.S. Special Operations Command white paper defines them as “competitive interactions among and within state and non-state actors that fall between the traditional peace and war duality . . . characterized by ambiguity about the nature of the conflict, opacity of the parties involved, or uncertainty about the relevant policy and legal frameworks.” 6 Gray zones pose a dilemma for nations such as the United States that maintain a bright line between law enforcement and military operations and carefully observe the international norms that revisionist actors contest. They are especially challenging in the maritime domain, where matters of authority, jurisdiction, and sovereignty compound the inherent difficulty of determining the nature and intent of an ambiguous threat. Since choosing the appropriate response requires first classifying a threat, sowing uncertainty can be an effective way to inhibit action.

The Coast Guard Advantage

Maritime gray zones are a challenge the Coast Guard is well poised to confront. As the only military service with law enforcement authorities, it can bridge the complex seam between constabulary and military operations that irregular actors seek to exploit. Many of the core competencies the Coast Guard hones match those required for countering irregular adversaries abroad. The Coast Guard can enhance regional maritime governance by engaging directly with the internal security forces of partner nations, providing different avenues of cooperation from the Department of Defense (DoD). Coast Guard cutters also are useful for strategic messaging in sensitive regions since their presence does not signal a belligerent intent.

The advantages of employing coast guards in gray zone environments are not lost on other nations. Indeed, the recent buildup of coast guard fleets by China, Japan, South Korea, and others has been labeled by some observers as “white hull warfare” and a “coast guard arms race.” 7 The evolving role of coast guards in the South China Sea signals a major evolution from historical measures of sea power that focused on combat power such as tonnage, broadside “weight of metal,” armor, speed, and maximum engagement range. China recently completed construction of the largest coast guard vessel in the world, which displaces more than a Ticonderoga (CG-47)-class cruiser yet has limited offensive capability. 8 Of course, China and its neighbors are building up their naval combat power as well, but the emphasis on using white hulls to enforce maritime claims signals a desire to avoid escalation or the perception of undue aggression.

While the U.S. Coast Guard is a natural fit for taking a prominent role in maritime gray zones, it remains severely limited by capacity. As the smallest U.S. armed service, charged with a diverse range of domestic statutory missions, the service must cast a skeptical eye toward any suggestion that it spread its forces thinner than they already are. Contentions that the Coast Guard routinely should deploy National Security Cutters to patrol the South China Sea, for example, do not hold up to cost/benefit scrutiny after analyzing the impact of their absence from priority missions in the Western Hemisphere.

By contrast, PATFORSWA is a template for a cost-effective, versatile maritime force package tailor-made for gray zone environments. Patrol craft operate at a fraction of the cost of a large surface combatant and are better suited for many littoral missions. The Navy discovered, for example, that its Cyclone (PC-1)-class patrol craft could fulfill many of the roles traditionally assigned to cruisers and destroyers in the Arabian Gulf to counterbalance the shift of large combatants to the Pacific. 9 A RAND study of the potential utility of using small ships for theater security cooperation roles concluded that vessels in the 300–700 ton range provided a desirable balance between cost and capability, with the added benefit of being able to interact with smaller navies and coast guards on a more peer-to-peer level. 10 Patrol craft also will wield more sophisticated capabilities in the future. Emerging technology and concepts such as autonomous systems and distributed lethality portend vast new possibilities for employing smaller vessels in traditionally big-ship roles. Still, the most important capability for engagement missions such as security cooperation will remain human-centric. Now and in the future, patrol craft need well-trained, well-led crews, in-depth knowledge of the operating environment, and finely honed instincts and judgment.


The Coast Guard is more accustomed to operating in the Straits of Florida than the Strait of Hormuz. Coast Guardsmen reflexively think in terms of law enforcement use of force rather than rules of engagement; preparing these personnel for expeditionary environments requires supplementing core domestic skillsets with in-depth area and mission-specific training. PATFORSWA uses a time-tested program to do so, but it has not matured very far beyond initial operating capability. Opportunity for improvement abounds.

Although the Coast Guard has been steadfast in providing cutters and support staff to PATFORSWA for the past 14 years, it continues to view the mission as a temporary niche role tied to continued overseas contingency operations (OCO) funding. Because OCO funds are uncertain from year to year, the Coast Guard has been reluctant to commit to evolving how it approaches the mission. Nor has it moved to translate the experience it has gained there into a sustainable skillset. Coast Guard members assigned to PATFORSWA complete a one-year tour and then rotate to other units. Once a member departs, there is no mechanism to sustain, grow, or capitalize on the skills gained during his or her deployment. As a result, rather than benefiting from 14 years of collective experience, PATFORSWA essentially has gained one year of experience 14 times.

The Coast Guard’s predeployment training program also remains stuck in the status quo. The program entails two months of just-in-time training that relies heavily on contracted support and emphasizes individual weapons proficiency and advanced boarding procedures, including close-quarters battle tactics. The regimen is intensive but not particularly well aligned with the in-theater mission profile. There is little to no underway training to practice decision making and surface engagement tactics or simulate realistic encounters with maritime Arabian Gulf actors. Scant time is devoted to studying the complex sociopolitical situation, regional history, or cultural nuances necessary for understanding the human terrain. And there is almost no mutual training or interaction between the Coast Guard and Navy patrol craft crews, even though they perform nearly identical missions side-by-side and operate similar platforms once deployed.

Returning to the 2015 riverine incident, the Navy’s investigation concluded that the predeployment training the crews received was adequate for the environment and mission. Several facts in the investigation, however, seem at odds with that conclusion. For example, many of the crew members said they were not aware of an IRGCN threat present in their area, or even that IRGCN interaction was a contingency that required consideration and planning. The crews did not demonstrate knowledge of preplanned responses, rules of engagement, or adherence to the Code of Conduct. However sufficient their training might have been in theory, it did not serve them well when it mattered. A more realistic assessment that simulated various worst-case scenarios might have revealed those readiness gaps before the units arrived in theater.

Comparing the Navy riverine crews’ predeployment training to the Coast Guard’s, the former appears to be more comprehensive in several respects. The question the Coast Guard must ask, therefore, is whether its own crews are fully prepared for worst-case scenarios. In doing so, the service must avoid the fallacy that because no dangerous training gap has revealed itself so far, none exists. A wiser approach would be to examine how effectively crew readiness for strenuous situations currently is assessed and validated.

A Way Ahead

PATFORSWA has demonstrated the value of forward-deploying patrol craft to gain littoral capacity, but the operational concept needs to evolve to reach its full potential as a gray zone force multiplier. An important first step must be for the Coast Guard and Navy to commit to developing the capability as a mutual, long-term investment.

PATFORSWA is an ideal opportunity to implement former Chief of Naval Operations Admiral Jonathan Greenert’s vision of joint force interdependence, which he describes as the “deliberate and selective reliance and trust of each Service on the capabilities of the others to maximize its own effectiveness.” 11 Coastal patrol craft fill a vital capability niche between nearshore patrol vessels such as the new Mark VI and offshore vessels such as the Littoral Combat Ship. The Navy’s only coastal patrol craft, however, are its 13 Cyclones, which will reach the end of their service lives in a decade, with no Navy program of record for a comparable replacement. 12 The Coast Guard, meanwhile, currently is recapitalizing its legacy Island-class fleet with 56 Sentinel-class fast-response cutters, which are a close capability match to the Cyclones. Acquiring Sentinels for a dedicated expeditionary role would be a cost-effective solution for the Navy to maintain coastal patrol craft in its inventory.

Replacing both the Island and Cyclone classes with a common Sentinel-based platform would bring the Navy and Coast Guard into closer alignment and even open the possibility of integrating crews based on mission demand. Toward that end, the two services should consolidate training, education, and doctrine for expeditionary littoral operations. PATFORSWA is a logical foundation to build on, starting with development of a common predeployment training program for the Navy and Coast Guard patrol craft crews. The Coast Guard’s deployable specialized forces and the Navy Expeditionary Combat Command already have set a precedent through their partial integration, yet many seams persist between the Coast Guard and Navy surface communities. Both services stand to gain a great deal from combining their respective strengths and eliminating redundancies. The Coast Guard’s expertise in constabulary missions added to the Navy’s prowess in expeditionary warfare would create a diverse skillset well suited for maritime gray zones.

A joint Coast Guard–Navy stateside training facility should serve as a “battle lab” focused on training and concept development to support forward-deployed squadrons. The facility would combine simulators, dedicated training platforms, and classroom instruction by subject-matter experts to hone proficiency across the full range of potential mission employment scenarios, from security cooperation and infrastructure protection to surface engagement and responses to provocations and ambiguous threats. Thus, all patrol craft crews would receive extensive “train as they operate” experience and have a thorough knowledge of their missions and environment prior to arrival.

Anticipated Obstacles

Implementing this proposal would require the Coast Guard to overcome at least two sources of contrary winds: internal resistance and public perception. Internally, a movement to align more closely with the Navy and commit to a permanent role in DoD-centric expeditionary missions is certain to generate antibodies. The Coast Guard’s multimission DNA means it must constantly reconcile the competing interests of its diverse subcommunities, many of which perceive expeditionary defense operations as too far removed from the service’s core identity and would limit the scope of Coast Guard operations to the Western Hemisphere. That perspective, however, does not account for the evolving scope of the Coast Guard’s role in the joint force or the reality that hybrid threats already exist within the Western Hemisphere. The United States will face gray zone challenges not only abroad, but also in its own backyard. The benefits gained by enhancing Coast Guard and Navy capability and capacity for expeditionary missions will translate directly into improved readiness for homeland security and homeland defense.

Taking on gray zone challenges, especially in a military role, also carries a risk to the Coast Guard’s external image. The American public already is sensitive to a perceived over-militarization of domestic police forces, which has contributed to a dangerous schism between law enforcement entities and some of the communities they serve. The Coast Guard always has walked a fine line with its dual law enforcement and military status. Gray zone challenges by definition make distinguishing between law enforcement and military operations difficult, thus Coast Guard units inevitably will have to make judgment calls with imperfect information that risk using either too much or too little force, with potentially severe repercussions. The Coast Guard must ensure it maintains public confidence by communicating a clear mission statement that links action to purpose and by demonstrating the highest level of professionalism in public interactions.


The riverine crew’s capture was embarrassing and regrettable, but it served an important purpose in reminding us that expeditionary maritime operations are inherently dangerous and unforgiving to the unprepared. There may yet be a silver lining to the incident if, in the aftermath, significant and lasting improvements to future mission readiness can be achieved.

1. “Iranian Capture of Riverine Command Boats (RCB)/Navy Sailors Jan2016,” https://foia.navy.mil .

2. USNI News, “Coast Guard Fires Single Warning Shot at Iranian Dhow,” 27 August 2014.

3. Coast Guard Patrol Forces Southwest Asia consists of six Island-class patrol boats and crews, administrative and support personnel, a Middle East Training Team, Advanced Interdiction Teams, and other deployable specialized forces operating throughout the U.S. Central Command area of operations.

4. The Navy up-armed and forward deployed to Bahrain 10 of its 13 179-foot Cyclone-class patrol craft, which perform many of the same missions as the Coast Guard’s six 110-foot Island-class cutters.

5. USNI News, “Carter’s Rebuke of Navy Budget Proposal Points to Split Between Service, DoD Priorities,” 17 December 2015.

6. U.S. Special Operations Command, White Paper: “The Gray Zone,” 9 September 2015.

7. Todd Crowell, “A Coast Guard Arms Race,” Real Clear Defense, May 23, 2015, www.realcleardefense.com/articles/2016/05/23/a_coast_guard_arms_race_109... .

8. Franz-Stefan Gady, “Beijing Builds ‘Monster’ Ship for Patrolling the South China Sea,” thediplomat.com, 13 January 2016, http://thediplomat.com/2016/01/beijing-builds-monster-ship-for-patrollin... .

9. USNI News, “U.S. Navy Trading Destroyers for PCs in 5th Fleet,” 3 July 2013.

10. Robert Button, Irv Blickstein, Laurence Smallman, David Newton, Michele A. Poole, and Michael Nixon, Small Ships in Theater Security Cooperation (Santa Monica, CA: RAND, 2008), 40-41.

11. Admiral Jonathan Greenert, U.S Navy, “Navy Perspective on Joint Force Interdependence,” Joint Force Quarterly no. 76 (January 2015), 10.

12. See Captain Tom Shultz, U.S. Navy, “Replace the PCs,” Proceedings 142, no. 7 (July 2016), 40-41.

Lieutenant Commander Allen is a cutterman assigned to the Office of Defense Operations at Coast Guard Headquarters. He previously commanded the Sentinel-class cutter USCGC William Flores (WPC-1103) and the USCGC Baranof (WPB-1318), an Island-class cutter forward deployed to Manama, Bahrain. He also served as the executive officer of the USCGC Tornado (WPC-14), a Cyclone-class patrol craft. Commander Allen is a 2014 graduate of the U.S. Marine Corps Command and Staff College.



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