By: Matt Tuchscher
Estimated reading time: 9 min
As August 2, 2019 approaches, the US and Russia seem steadfast in following through with the termination of the Intermediate Nuclear Forces (INF) Treaty. August 2 marks the end of the mandatory 6 month notification period, as described by Article XV of the INF, based on the US intent to withdraw from the INF Treaty that was delivered on February 2.
Since 1987, the treaty has prohibited the development of land-based ballistic and cruise missiles of “shorter-range” and “intermediate-range” for both the US and Russia. Despite the inclusion of the word “nuclear” in the title, the INF Treaty bans all ballistic and cruise missile ranges between 500 and 5500 km, both nuclear and conventional.
While the US and Russia may eventually reach a new arms control agreement, such an arrangement will be unlikely without the cooperation of a broader group of signatories. In particular, the US is likely to demand the incorporation of the People’s Republic of China (PRC) in any future deal, since the PRC has enjoyed relatively unconstrained missile development as a means to exert its increasing power in the Pacific.
As a result of the complex uncertainty surrounding the future of the INF, it is prudent to examine likely US military outcomes in a post-INF scenario. Even a temporary lapse in the INF could spur a complex arms race with broad implications as both the US and Russia compete to leverage this new advantage. For example, the US is reportedly already preparing to test land-based Tomahawk cruise missiles (Figure 1) in August 2019 with longer range ballistic missile tests in November 2019. Both of these tests would otherwise be banned under the current INF construct.
Although much has been written about whether or not the INF should be dissolved, what a post-INF world could actually look like remains relatively opaque. Therefore, instead of summarizing the current debate, this article seeks to coarsely map the post-INF possibility frontier for the US military. This article poses three expected short-term outcomes and then projects these outcomes forward to develop three operational implications.
Of note, this article does not specifically address hypersonic weapons, although many of the following concepts would be applicable.
Outcome 1: Accelerated Missile Stockpiling
Termination of the INF is likely to spur a significant net increase in intermediate-range missiles overall. Under the INF, missiles with ranges between 500 and 5500 km are constrained to air and maritime forces only. As a result, the demand for missiles is capped by the capacity of the existing air and maritime assets to employ them given expected wartime scenarios, force generation rates, and expected timelines. This capping effect is compounded by the high opportunity cost associated with carrying missiles on multi-mission assets.
The US military could opt to immediately procure land-based variants of existing weapon systems both to augment air and maritime assets and to provide latitude for these assets to execute competing missions. For example, land-based missile systems could be forward deployed as a long-term deterrent without committing a persistent air or maritime presence of similar magnitude.
Near-term implementation examples include the resurrection of the aforementioned land-based Tomahawk GLCM (Figure 1/Cover Photo) or the conversion of Aegis Ashore (Figure 2) into a weapon system that is capable of both offensive as well as defensive employment. This conversion could have immediate implications for the European theater and appears to be technically viable due to commonality with maritime Aegis platforms, including the MK 41 Vertical Launching System (VLS).
Outcome 2: Longer Range Missile Variants
In addition to the development of new ballistic missiles, the end of the INF is also likely to result in both range and persistence improvements for land-based variants of existing missiles. These range and persistence improvements could be garnered by increasing fuel capacity for derivatives of weapons that are still in production by taking advantage of less constrained weapon sizes. This is because existing missile sizes and the resulting ranges are constrained by practical considerations for form and fit with existing air and maritime platforms.
For example, although the B-1 aircraft can carry twenty-four AGM-158 Joint Air-to-Surface Standoff Missiles (JASSM), the physical size of the missiles and the resultant range has been constrained to allow for internal carriage of the missiles (Figure 3). Although size may be less of a constraint for maritime assets, weapon compatibility with existing systems like the MK 41 VLS still imposes a significant design limit.
Figure 4 provides example unconstrained missile sizes for both medium and intermediate-range ballistic missiles as given by the 2019 Missile Defense Review. Range and persistence improvements could come from increased fuel capacities, unconstrained wing designs, or other modifications that possible with less prohibitive land-based systems.
Outcome 3: Diverse and Modular Payloads
As a result of combining increased missile numbers with increased ranges, modular payload diversification is likely to emerge out of necessity. As a result, families of missiles with varying payloads are highly likely. Possibilities include various kinetic and non-kinetic payloads; diverse sensors; electronic warfare; and sub-payloads, to include drones. In addition, new missiles will likely incorporate a combination of networked, collaborative, and semi-autonomous systems to offset the long times of flight associated with intermediate-range missiles and the increasingly dynamic nature of enemy defenses.
Low-cost systems; collaborative autonomy and swarming; and low-cost, networked cruise missiles are all supported by the USAF 2019 Science and Technology Strategy (Figure 5). Furthermore, the 2019 Missile Defense Review calls for “attack operations for missile defense” which includes investing in options to promptly strike fleeting targets at stand-off ranges, both with currently available capabilities and new concepts.
If missiles are to operate at significant range with limited external support, missile packages will need to incorporate combinations of capabilities to effectively execute the kill chain while simultaneously countering enemy defenses. Many of these concepts and the resultant salvo strategy are well summarized by the Center for Strategic and Budgetary Assistance in “Winning the Salvo Competition: Rebalancing America’s Air and Missile Defenses”.
Implication 1: Option to Reduce High-Risk Forward Basing of Air Assets
The combination of above-mentioned outcomes creates an opportunity for the US military to exchange some forward positioning of short-range air assets for the deployment of dispersed land-based missiles. This implication could allow the US military to reduce operational risk by providing an alternative to forward basing of short-range air assets or forward aircraft carrier placement. This option is particularly critical prior to the initiation of hostilities when the enemy poses a credible missile or air threat that could range these positions.
Land-based missile systems could reduce the overall risk to the forward force by partially removing the obvious vulnerability of aggregated air assets in close proximity to an enemy force. Furthermore, since dispersed and dynamic missile systems are theoretically harder to target than aircraft at fixed airfields, the US military could maintain a credible deterrent with a smaller overall forward force.
An obvious consideration is the complexity of projecting direct lethal force from sovereign states as opposed to international airspace, which could create challenging deterrence and escalation dynamics. However, the overall benefits in “anti-access” scenarios may outweigh the risks, particularly when the enemy has a robust Integrated Air Defense System (IADS) and the capability to project force at substantial ranges relative to the unrefueled range of US air assets.
Implication 2: Partial Convergence between UAVs and Missiles
An end of the INF is also likely to accelerate a partial convergence between UAVs and missile systems. This is heavily driven by the increased persistence and modular payload outcomes discussed above. In addition, as the option to reduce high risk basing becomes more attractive, land-based missile systems will likely evolve to provide the capability to launch highly capable and recoverable platforms without robust runways and infrastructure.
An example system that launches UAVs via a missile-type apparatus is the Office of Naval Research’s Low-Cost UAV Swarming Technology (LOCUST) system. This system is now under development at Raytheon as the Coyote UAS (Figure 7). Although this short-range system is not directly affected by INF termination, it serves as a proof of concept for missile-launched UAVs. As payload diversification increases, both missiles and UAVs are likely to increasingly leverage low-cost mass as a means to counter-balance expensive and highly complex defensive systems.
Another example is the Israel Aerospace Industries (IAI) Mini Harpy munition (Figure 8). This persistent weapon reportedly endures for extended periods while using an array of sensors to locate and target enemy emitters. Of note, IAI is advertising that the Mini Harpy provides the option to integrate with remote operators who can use the munition to collect intelligence or provide targeting guidance and control to the weapon.
Implication 3: Dynamic Missile Packaging and Employment
The final likely implication is a demand for increased dynamic long-range missile employment and force packaging in conjunction with manned maneuver. As land-based missiles alleviate the demand for high-risk forward positioning, the necessity to integrate land-based dynamic weapons with manned systems will naturally increase.
At present, long-range munitions are often viewed as preparatory fires for follow-on operations, since they are limited in quantities and challenging to employ dynamically at acceptable risk levels. However, as long-range weapons and manned assets become increasingly interoperable, land-based missile systems provide opportunities to enhance manned effectiveness more dynamically.
For example, mixed salvo land-based munitions could act as penetration aids to reduce risk to manned strike assets. In this case, an aircraft may still be required to achieve desired weapons effects; however, manned force packaging requirements could be alleviated by a mixed salvo of decoys, jammers, sensors, and munitions. One such example of investment in this area was the US Air Force Research Laboratory (AFRL) $110 million contract for Lockheed Martin to develop the Gray Wolf project in 2017 (Figure 9). This initiative reportedly aspired to integrate networked and collaborative missile salvos with fighter and bomber aircraft. Another example is the Defense Advanced Research Projects Agency (DARPA) System of Systems (SoS) concept.
Finally, land-based missiles could help to alleviate limited weapon carriage on manned air assets. This could be particularly viable for dynamic targeting in highly contested environments. This is similar to the arsenal plane concept that seeks to augment limited weapon carriage by integrating long-range standoff munitions with close-range sensors on more survivable platforms.
In summary, if the INF is indeed terminated, the US military is likely to pursue new approaches to maximize return in this area. Likely outcomes include missile stockpiling, long-range variants, and diverse modular payloads. Resulting implications include options for reducing high-risk forward basing of air assets, an accelerated partial convergence between UAVs and missiles, and an increased demand for dynamic missile packaging and employment. Overall, the end of the INF Treaty is likely to catalyze a complex arms competition as both the US and Russia overtly leverage this new advantage to check one another as well as previously unconstrained states like the PRC.
Major Matt “Fold” Tuchscher is a student in the Multi-Domain Operational Strategist concentration at Air Command and Staff College.
The views expressed are those of the author and do not reflect the views or official policy of the Department of the Air Force, Department of Defense, or any organization in the United States government.