Episode 20: We can shoot down nuclear weapons, right?

Summary:

In this episode we debunk common misconceptions about the ability to intercept nuclear missiles. We explain that recalling or aborting a launched ICBM or SLBM is impossible, and that shooting them down in flight is unreliable due to the complexity of their flight phases and the effectiveness of countermeasures. We also highlight the challenges of intercepting tactical nuclear weapons, particularly those with hypersonic capabilities, due to their short range, low altitude, and high speed, making detection and tracking extremely difficult.

 Questions to consider as you read/listen:

1. What are the different phases of a nuclear missile's flight, and how do they affect our ability to intercept it?
2. What are the limitations of current missile defense systems in intercepting nuclear missiles, and what are the potential solutions?
3. How does the development of new, non-ballistic nuclear weapons, like hypersonic missiles, challenge existing missile defense systems?

Long format:

But we can shoot down nuclear missiles, right?

Some myth busting. 

Myth #1: You can recall, redirect, abort or self destruct a nuclear ICBM or SLBM. 

 Truth: No you can’t recall or abort a nuclear ICBM or SLBM once it has been launched. I’m sorry Spies Like Us the great movie that it is lied to you. (sources: https://spectrum.ieee.org/nuclear-war#:~:text=Today%20the%20delivery%20of%20a,they%20are%20on%20their%20way and https://www.ucsusa.org/sites/default/files/attach/2015/01/Hair-Trigger%2520FAQ.pdf)

 Myth #2: You can shoot down ICBMs or SLBMs in flight:

 Truth: Not reliably. 

 In order to understand this as a problem, you have to appreciate the basic nature of ballistic weapons. The three phases of flight for an ICBM are: boost phase, midcourse phase, and terminal phase.

 The boost phase is the initial phase where the missile's engines fire to accelerate it to the necessary velocity to reach its target. Typically at altitudes between 150 and 400 kilometers (93 to 249 miles).

 The midcourse phase is once the engines shut off, the missile continues its trajectory through space, typically at a high altitude, with no propulsion. Reaching apogee (highest point) at around 1,200 kilometers (750 miles) altitude. 

 The terminal phase is the final phase where the missile re-enters the atmosphere and descends towards its target. Begins re-entry into the atmosphere at around 100 kilometers (62 miles) altitude.

 The Holy Grail in anti-ballistic missile defense against ICBMs is to intercept during the boost phase (Boost Phase Intercept-BCI). The boost phase, is ICBMs most vulnerable and easiest to target during this early stage of flight when its rocket engines are still firing. In the boost phase the target is a large, hot booster that is moving more slowly. BPI also eliminates the problems of dealing with multiple warheads or submunitions or decoys.

 In the next phase the mid course phase, modern nuclear ICBMs place the nuclear warhead in a metal-skinned balloon surrounded by dozens of similar decoy balloons would thoroughly disguise it to radar and to the seeker on the homing kill vehicle of the interceptor missile. Plus, it is where multiple independently targetable reentry vehicles (MIRV) are deployed.

 Currently the best strategy is to concentrate on intercepting at the midcourse phase because BCI is not capable due to deployment issues and intercept times and the OODA loop. Intercepting in the terminal phase is not a great strategy. The terminal phase is very short, with an intercept time of less than 30 seconds. The MIRVs or the single warhead are small and are moving incredibly fast. Over 15,000 mph. And if the intercept happens during the terminal phase there will be a release of nuclear materials whose damage/consequence depends on the altitude and conditions. So it’s not optimal.

 There are several advantages of a midcourse intercept and why it is attractive. The boost phase lasts about 3-5 minutes. The midcourse phase lasts longest, under 20 minutes. As such, it offers more opportunities to intercept the missile. If the first intercept attempt fails, more shots can be taken. There terminal phase is under 2 minutes.

 When there is a ICBM launch, within 5 minutes, the US Missile Defense Agency in Fort Belvoir, MD is provided data to try to engage the Ground-Based Midcourse Defense System (GMD) and in the case of a Pacific or Arctic transit using the SBX.  launching from US Army Space and Missile Defense Command in Fort Greeley, Alaska. 

 The GMD has been a resounding disappointment. The GMD system has a 55% success rate in very highly-scripted tests, but has missed in the last six tries. The US Army has tacitly admitted defeat, I think, in that there are only 44 ground-based missile interceptors housed at two military bases (Fort Greeley, Alaska has 40 and Vandenberg Space Force Base, California has 4), not hundreds or thousands. It is a three-stage solid rocket booster to fly out of Earth's atmosphere at near-hypersonic speeds. At one time, the kill component of the kill  was in space and was a kinetic event involving the Raytheon Exoatmospheric Kill Vehicle (EKV) which had very large difficulties (it was off course by a lot) The successor replacement is the Redesigned Kill Vehicle (RKV) which may be deployed in 2025.

 As great as the THAAD system is, it has not been found to be conclusively effective to intercept ICBMs. Its very technology is for short, medium and intermediate range ballistic missiles and not true ICBMs. The THAAD interceptor reportedly “carries no warhead” and relies on physically striking its target to defeat it. It is a kinetic killer which has not been proven to be optimal against ICBMs, see the above. 

 Sources:

https://armscontrolcenter.org/issues/missile-defense/gmd-frequently-asked-questions/

 

 

The US isn’t the only folks trying to work on this. The other ones of note include:

 

The Russian A-135 anti-ballistic missile system which is deployed around Moscow was originally armed with nuclear warheads, but were updated in 2017 to use non-nuclear kinetic interceptors. Russia is very guarded about its efficacy. To date in the public record is one and only one successful test of an intercept. But what are the details? Did it in fact intercept a ICBM or just launch. Unknown.

 

Source: https://missilethreat.csis.org/tag/a-135/  and https://tass.com/defense/1228071  and https://sputnikglobe.com/20201126/russian-military-successfully-tests-new-anti-ballistic-missile-1081278309.html ) 

 

The Israeli Arrow 3 system is touted as being capable of intercepting ICBMs during their spaceflight portion of their trajectory (midcourse phase). It is also a potential anti-satellite weapon. It has intercepted some of Iran’s exoatmospheric missiles (which are long-range ballistic missiles), but these are not ICBMs at ICBM altitudes and speeds.

 

The Indian Prithvi Defence Vehicle Mark 2 has completed developmental trials and is awaiting government clearance for deployment. Other than opaque claims that it has been tested multiple times over years, the exact efficacy of this system against a true ICBM appears to be not of public record. All of the public record tests were not for ICBMs and not during the midcourse phase.  

 

Sources: https://www.usiofindia.org/publication-journal/Evolution-of-India-Ballistic-Missile-Defence-Program-Prospects-and-Challenges.html#:~:text=India's%20BMD%20shield%20is%20basically,the%20enemy%20missile's%20launch%20trajectory and https://www.ndtv.com/india-news/interceptor-missile-test-fired-successfully-449178

 

 Myth #3: Shooting down a tactical nuclear weapon is possible.

 Truth: The very basis of a non ballistic tactical nuclear weapon especially a hypersonic one is as follows:

 

1. very short range (300 miles or way less) deployment 

 

2. At incredibly at very low altitude (cruise) (30–90 meters (100–300 feet AGL)

 

3. at very fast speeds (hypersonic) )(greater than 3000 mph and Mach number M greater than five, M > 5)

 

Number one and three make the maximum flight time at 3000mph and at the max 300 miles that’s 6 minutes max. 

 

Flying at 30–90 meters (100–300 feet AGL) makes detection exceedingly difficult to detect and track. In fact they require very special radar to POSSIBLY detect them. 

 

All resulting in no apogee as its non ballistic in nature meaning no boost phase, no midcourse phase, and no terminal phase therefore defying all current means of interception which are non existent in boost phase, less than 50% successful in the midcourse and generally most successful in boost (provided not too many or going too fast). 

 

So the opportunity to observe is very short and unlikely and therefore your OODA loop is non existent. 

 

So yes it’s a cat and mouse but the cat is by far the winner and there’s 

 

Source:

https://www.ipcs.org/comm_select.php?articleNo=2337#:~:text=Further%2C%20it%20is%20very%20difficult,track%2C%20identify%20or%20engage%20them

 

https://armscontrolcenter.org/wp-content/uploads/2017/04/Ballistic-vs.-Cruise-Missiles-Fact-Sheet.pdf

 

https://missiledefenseadvocacy.org/missile-threat-and-proliferation/missile-basics/cruise-missile-basics/#:~:text=Their%20low%20flight%20path%20makes,and%20track%20high%20altitude%20threats.%20%5B

 

https://www.popsci.com/technology/cruise-missile-defense/

 

https://archive.ll.mit.edu/publications/journal/pdf/vol12_no2/12_2detectcruisemissile.pdf

 

https://missiledefenseadvocacy.org/defense-systems/boost-phase-missile-defense/#:~:text=Boost%20phase%20missile%20defense%20entails,a%20geographic%20and%20engineering%20standpoint