With a Massive Next-Gen Interceptor, America's Missile Defense Has Entered a New Era (2024)

In April, the wheels of the Pentagon’s decades-long quest to develop an effective ‘missile shield’ for the United States ground a bit further forward (uncharacteristically, even ahead of schedule).

The Missile Defense Agency announced that Lockheed-Martin (in partnership with Rocketdyne/L3Harris) had been chosen over competitor Northrop-Grumman to lead the $17.7 billion program to build a second-generation nuclear-missile-killing weapon dubbed the Next Generation Interceptor (NGI). The first of the 20 NGIs that the Pentagon plans to procure could be delivered by 2027.

The award came a year sooner than planned—before the competitors’ Critical Design Reviews were even finalized. MDA leader Lt. Gen Heath Collins told Congress that the accelerated selection was due both to budgetary developments (i.e. a half-billion dollar cut to MDA funding in 2024) and to that fact that the agency had already largely made up its mind.

Compared to the current inventory of 44 Ground Based Interceptors (GBIs) deployed in Alaska (as part of the GMD system protecting the continental U.S. from nuclear missiles), the future NGI missiles should exhibit a much lower failure rate. They should also be better able to discriminate against decoys and latch onto missiles that maneuver evasively. New rocket boosters are additionally involved in improving engagement flexibility and general kinematic performance.

But above all, Pentagon budget documents confirm that each NGI interceptor will carry multiple anti-missile kill vehicles (EKVs) instead of just one. That may not only improve interception rate for regular missile targets, but allow NGI interceptors to deal with enemy missiles designed to release multiple nuclear warheads known as Multiple Independent Reentry Vehicles, or MIRVs.

For example, a Russian RS-18 Stilleto ICBM can carry six MIRVs, each with a 400-kiloton warhead—roughly 20 times the yield of the Fat Man bomb dropped on Japan in 1945. So, basically, every MIRV that gets released poses a huge threat.

The MDA is also developing a separate missile defense system called Glide Phase Interceptor (GPI), and the race for that contract has Northrop Grumman competing against RTX. GPI will be designed to intercept hypersonic glide vehicles, which also have potential as long-range strategic nuclear weapons, but differ from ICBMs in flight profile and maneuverability.

Why was Northrop-Grumman lose the NGI contract?

Northrop-Grumman’s loss surprised some industry observers due to the fact that the company has a larger footprint in the space sector than Lockheed—particularly as it acquired the missile-builder Orbital ATK, which builds the boost vehicles for the current GBI interceptors (the branch is now renamed ‘Space Systems’), in 2018. Northrop-Grumman has also secured the massive contract build the U.S.’s next-generation LGM-35A Sentinel intercontinental-range ballistic missile, also known under the program name Ground-Based Strategic Deterrent, or GBSD.

But according to an industry insider with high-level connections inside Northrop-Grumman, the Sentinel program may not have exactly played in the company’s favor.

“The loss may have taken people by surprise because even though Lockheed-Martin isn't thought of as a ‘space company’ as much as Northrop-Grumman Corporation is,” the source said. “But [Lockheed] still has a lot of experience in [ballistic missile] interceptors and air defense (THAAD, Patriot PAC-3, and AEGIS combat system) and likely offered a better price than Northrop Grumman did.”

Furthermore, if the competition used past performance as a metric, Grumman’s work on Sentinel “probably doesn’t look all that great,” as Sentinel want far over budget.

Ironically, the source added, the combination of GBSD’s skyrocketing costs, its divestment of NGI, and its up-front R&D costs may actually improve Northrop-Grumman’s short-term fiscal outlook. The source also noted that layoffs of 1,000 employees in Northrop-Grumman’s Space Park facility in Redondo Beach, CA were most likely not related to the NGI loss, as that facility wasn’t involved in its development.

Meanwhile, Lockheed's NGI program reportedly spearheaded the company’s $6 billion internal 1LMX initiative to comprehensively retool its design process with digital computer modeling—often using new software tools built in-house. Allegedly, these tools enabled speed and cost efficiencies which may have helped Lockheed secure the win on NGI. Both Lockheed and Northrop-Grumman also opened new facilities in Huntsville, Alabama to work on NGI and other space-oriented programs.

Correction: This article originally connected NGI to a reported $100 million dollar loss in Lockheed's Missile and Fire Control (MFC) division. However, this loss was actually related to classified program in MFC, not NGI, which has in fact contributed to growth.

Can the new NGI missile protect the U.S. from a nuclear attack?

In the 2000s, the United States first deployed (at great expense) a limited national missile defense system called Ground-based Midcourse Defense (GMD). It featured 44 interceptor missiles based at Fort Greeley, Alaska, which was run by the Alaska Army National Guard's 49th Missile Defense Battalion.

Detection and tracking of enemy missiles was undertaken by forward-deployed AN/TPY-2 radar, the gigantic floating Sea-Based X-Band radar, and a discrimination radar in Alaska. Command control direction, on the other hand, was provided by elements of the 100th Missile Defense Brigade in Vandeberg, California and Colorado Springs. Once interception was authorized and calculated, GBI interceptors rocketed off from their silos, attaining ridiculous speeds of up to Mach 33 (thanks to their three-stage rocket boosters). Then, they released a maneuverable exo-atmospheric kill vehicle (or EKV) designed to leverage infrared guidance, and precisely rammed an incoming nuke during its midcourse flight phase in outer space.

That GMD could kill ICBMs at all was groundbreaking—a feat much harder than hitting a rifle bullet traveling at Mach 2 with another rifle bullet, as the speeds involved are over an order of magnitude greater. But the GBIs had a less-than-stellar 57% success rate in tests, and critics have long expressed doubts that GBIs will reliably intercept more advanced ICBMs that deploy decoys, perform evasive maneuvers, or release a scatter shot of MIRVs.

Even ordinary missile debris, such as jettisoned rocket boosters and other components, must be discriminated against by fire control crew members to ensure that the precious interceptor engages the genuine threat.

As a result, multiple GBIs were likely to be launched to ensure the destruction of a single missile, meaning that the ‘ammo depth’ of GMD might prove even smaller than it seemed. This is a problem that the NGI missile is hoping to address with its modest expansion of inventory (from 44 to 64 interceptors).

It’s worth noting the U.S. Navy also deploys several hundred of SM-3 Block IIA missiles on its destroyers and cruiser, which are moderately capable of midcourse ICBM interception around a more limited radius. Such vessels could theoretically be pre-positioned to supplement defense of specific regions of the U.S. from ICBM attacks, at the expense of performing other operational roles.

To build a better nuclear missile interceptor

Originally, the Pentagon planned an intermediate upgrade of GBI called the Block 3 Redesigned Kill Vehicle (RKV), which was estimated to cost $5.8 billion. But this was cancelled in 2019, along with the dependent Multi-Object Kill Vehicle program intended to defeat MIRVs and decoys.

The plan for NGI that followed involved an all-new interceptor missile that wouldn’t inherit the intrinsic flaws of the original GBI design. This was assessed to cost $17.7 billion for delivery of 21 new missiles in 2027-2028. That implies a steep (nearly billion-dollar) cost per missile shot—steep, unless those shots end up saving a metropolis from being hit by a nuke, that is.

In truth, the Pentagon still sought an upgrade to its older GBIs, which Northrop Grumman and Lockheed provided by 2021, in the form of a new option to release the interceptor’s kill vehicle earlier after the second rocket booster stage. The goal was to trade speed for time and maneuverability, making it more effective versus more evasive targets. A successful two-stage intercept test of an intermediate-range ballistic missile was conducted at Vanderberg, CA on December 11, 2023—one that involved the 61^st and last GBI ever produced, which had been delivered earlier that year.

Back in 2022, the MDA also completed construction of Missile Field 4 in Alaska, which will add 20 missile-launching silos for the forthcoming GBI missiles.

The enigma of strategic missile defense: how little is too much?

GMD’s planned future force of 64 interceptors remains focused on defending against a small-scale ICBM attack from North Korea or Iran, should the latter ever deploy a nuclear-armed ICBM-class missile. Those countries aren’t expected to be able to build enough ICBMs to overwhelm GMD.

The small size of the U.S.’s anti-ICBM interceptor inventory was intended to persuade Russia and China (which possess thousands and hundreds of nukes, respectively) that GMD wasn’t intended to undermine the deterrence provided by their much larger nuclear arsenals.

However, neither China nor Russia perceived it that way. Now, U.S. adversaries large and small alike (China, Iran, North Korea, and Russia) have all begun testing diverse new ways to deliver nuclear attacks to the continental United States. Those include hypersonic glide vehicle weapons (which might be launched fractional orbital bombardment systems), slow but long-range aerial drones, strategic nuclear drone torpedoes, and exotic cruise missiles. They may also be incorporating MIRVs into ICBMs.

Overall, NGI has the potential to considerably improve the per-shot effectiveness of the U.S.’s limited national missile defense. In addition to throwing the ability of minor nuclear powers to attack the U.S. into question, it may have the effect of dissuading even major nuclear powers from considering a small-scale “demonstration” attack against targets on U.S. soil. That said, it’s debatable whether such ‘signaling’ usage of strategic weapons intended to deter escalation is seriously considered, due to the risk it might backfire and provoke overwhelming nuclear retaliation.

Furthermore, there’s already an observable ‘balloon effect,’ in which advancements to the ability to shoot down ICBMs cause adversaries to redirect nuclear arms development towards new delivery systems designed to bypass GMD. Lastly, there’s the possibility that North Korea (or, hypothetically, Iran) may attempt to build an ICBM force exceeding the capacity of GMD, despite predictions that they couldn't afford to do so.