The United States has conducted a successful test, FTT-18, of the Terminal High Altitude Area Defense (THAAD) system in Alaska. FTT-18 was long planned for 3rd quarter 2017. The THAAD interceptor dispensed a kill vehicle that struck an Intermediate Range Ballistic Missile target for the first time. THAAD is a critical layer in the multi-layered Ballistic Missile Defense system, designed to engage in their terminal phase of flight, at high altitude, of medium and intermediate range ballistic missiles.
We need to stress that the test was successful within the set parameters of the exercise.
The Missile Defense Agency, by contrast, has strongly implied that the test serves as a demonstration of the combat readiness and capability of THAAD against IRBMs in particular
“This test further demonstrates the capabilities of the THAAD weapon system and its ability to intercept and destroy ballistic missile threats. THAAD continues to protect our citizens, deployed forces and allies from a real and growing threat”
The MDA press release then explicitly states that the test demonstrated the combat readiness of THAAD when it uses the phrase “threat representative” in this passage
Preliminary indications are that planned flight test objectives were achieved and the threat-representative, intermediate-range ballistic missile (IRBM) target was successfully intercepted by the THAAD weapon system
It is argued that the test demonstrates this because the 11th Air Defense Artillery Brigade was not aware of the launch timing of the IRBM target.
However, as the press release states and the accompanying video, embedded below also shows, the IRBM target was launched from a cargo aircraft and the target warhead did not separate from the missile. That is not a threat representative target, at least not if we take by threat North Korea.
THAAD has a few limitations that we need to be cognisant of, especially given the evolving strategic dynamic in Northeast Asia. Regarding North Korea THAAD batteries are deployed in South Korea, Guam, and Hawaii. One of the most oft cited strategies that an attacker might employ to defeat ballistic missile defence is to saturate the system.
In so far as South Korea is concerned, important from a strategic perspective because a North Korean capacity to hold South Korean targets at risk provides Pyongyang with a nuclear deterrent, the North could use its fleet of Scuds, Scud-ERs, and Nodongs to saturate the AN/TPY-2 radar, especially when the interceptors are being sent updated data as part of a shoot-look-shoot strategy.
We saw earlier this year, during joint US-South Korean military exercises, North Korea simulate a barrage attack by firing 4 Scud-ER missiles simultaneously. Doubtless 4 isn’t sufficient to overwhelm THAAD, but the exercise demonstrated a capability North Korea needs to possess in order to overwhelm THAAD’s sensors. It is no less “threat representative” than FTT-18, perhaps more so.
Furthermore, two THAAD batteries in South Korea (2 additional launchers have been suspended by South Korea at time of writing this post. A THAAD battery has six launchers) might theoretically deal with an MRBM and IRBM launched from the North if fired on a standard and depressed trajectory, but that does not apply in the case of a high angle lofted trajectory. That consideration puts North Korea’s recent testing in perspective, as the lofted trajectories have implications for BMD. They are not simply a matter of addressing over flight concerns.
The Pukugsong-1 sea launched medium range missile is important in any assessment of THAAD, for the THAAD system can identify and engage targets within a 120 degree cone. THAAD’s sensors are pointed North, into North Korea, and an attack from a submarine launched Pukugsong-1 in the waters around South Korea would give the North an all azimuth capability, which is something THAAD in South Korea is unable to address. The Pukugsong-1 is a developmental programme, and so far as we know no North Korean submarines have been combat ready fitted with the Pukugsong-1. However, it needs to be considered in the THAAD context.
The KN-17 variant of the Scud-ER is a terminally guided missile, and it may well have a MaRV capability, and FTT-18 certainly was not representative with respect to the KN-17. The KN-17 is in development and its testing has been patchy but its emerging development needs to considered in the context of any assessment of THAAD.
Finally, the FTT-18 THAAD test, because it did not feature a separated warhead, did not establish THAAD’s capability of distinguishing between warhead and decoys in a representative threat cloud.
In sum, we should be a little bit sceptical about the implications that some draw from this THAAD test. THAAD, even if it worked as advertised, would not provide a 100% probability of kill for each and every warhead launched by the North against the South. THAAD works to the extent that it is able to support other military operations directed toward degrading and destroying Pyongyang’s strategic nuclear capabilities.
THAAD adds another facet to the evolving use them or lose them dynamic that is emerging on the Korean peninsula, which I have commented upon in previous posts, and if THAAD did work as advertised then that would be the worst possible situation as Pyongyang would have a very, indeed overwhelming, incentive to strike first in a crisis.
Others have commented that the timing is fortuitous because it sends a message of capability to North Korea at a time of tensions marked by high tempo North Korean missile testing. I myself adopt a different view. That timely message is primarily for the people of the United States whose consent is needed for the indefinite pursuit of a policy pursued by Washington that significantly risks their security, but not just theirs we might add.