Comparing Bunker Buster Capabilities of the US, South Korea, and Israel

 

Comparing Bunker Buster Capabilities of the US, South Korea, and Israel

Bunker busters are specialized weapons designed to destroy deeply buried and hardened enemy facilities. Because simple explosive power alone is insufficient to effectively target underground structures, bunker busters primarily rely on powerful penetration capabilities and delayed detonation.

Here's an in-depth analysis of the bunker buster technologies and operational statuses of the United States, South Korea, and Israel.

Principles of Bunker Buster Operation and Characteristics

The core operating principles of a bunker buster are as follows:

1. Penetration:

   • Utilizes the kinetic energy of a massive, ultra-high-speed falling projectile to pierce through concrete, soil, rock, and penetrate deep underground.
   • Unlike conventional bombs, bunker busters focus on penetrating as deeply as possible into the target before detonation.
   • The warhead is constructed from extremely robust alloys, designed to withstand the immense shock and high temperatures generated during penetration.

2. Delayed Detonation:

   • An internal delayed fuze is designed to detonate when it reaches a pre-set time or depth.
   • This ensures that the bomb explodes within the core of the underground facility, maximizing its destructive power.
   • A "daisy chain" or sequential targeting tactic is also sometimes used, where the first bomb creates a hole on the surface, allowing subsequent bombs to penetrate even deeper through that hole to destroy extremely hardened underground facilities.

3. High-Performance Insensitive Explosives:

   • The interior uses high-performance insensitive high explosives (IHE) that maintain stability even under high shock and temperature. This prevents premature detonation during the penetration process.

Analysis of Bunker Busters by Key Countries

1. United States (USA)

The United States possesses the world's most advanced bunker buster technology, with the GBU-57 MOP (Massive Ordnance Penetrator) being a prime example of its ultra-large penetrating bombs.

• GBU-57 MOP:
  • Weight and Size: Weighing over 13 tons (approximately 30,000 pounds) and measuring 6.2 meters in length, it is the largest conventional bunker buster in existence. Due to its size and weight, only the U.S. Air Force's B-2 stealth bomber can carry and deploy it, with a maximum capacity of two bombs per B-2.
  • Penetration Capability: It is known to penetrate over 60 meters of 5,000 psi reinforced concrete and up to 200 meters of natural rock. This makes it optimized for destroying deeply buried nuclear facilities or command and control centers.
  • Combat Deployment: It is reported that the GBU-57 was used in combat for the first time in an airstrike on an Iranian nuclear facility in June 2025. Tactics involving successive drops of multiple bombs on the same point were employed to achieve deeper penetration.
  • Operational Strategy: The combination of the stealth-capable B-2 bomber and the GBU-57 is considered an ideal pairing for precisely striking underground facilities without detection by the enemy.
• Other Bunker Busters: The U.S. also possesses various other penetrating bombs such as the GBU-28, GBU-37, and BLU-113. While smaller than the GBU-57, they still boast significant penetration capabilities (e.g., the GBU-28 can penetrate over 6 meters of concrete).
• Nuclear Bunker Buster: The B61 Mod 11 is the world's only "nuclear" bunker buster, reportedly able to penetrate several meters underground and, through its shockwave, destroy subterranean structures up to 300 meters deep.

2. South Korea (South Korea)

South Korea has focused on developing its own bunker buster technology to counter North Korea's deeply fortified underground facilities and nuclear program. It particularly boasts world-leading technical capabilities in missile-based bunker busters.

• Hyunmoo-5:
  • Warhead Weight: Dubbed the 'monster missile,' the Hyunmoo-5 is a formidable surface-to-surface ballistic missile with a warhead weighing a staggering 8 tons, making it one of the largest in the world. This represents an overwhelming power compared to the typical 1-ton warhead of conventional ballistic missiles.
  • Penetration Capability: While the exact penetration capability has not been officially released by military authorities, it is assessed to be able to penetrate much deeper than the U.S.'s GBU-57 (which penetrates 60 meters underground). It has been developed to the extent that it can destroy North Korea's underground command and control centers or nuclear facilities up to 100 meters deep.
  • Operational Method: As a surface-to-surface ballistic missile, it is launched from a ground launcher rather than dropped from an aircraft. It utilizes a cold launch method, making it harder for the enemy to detect, and its operation from a Transporter Erector Launcher (TEL) enhances its survivability.
  • Strategic Significance: For South Korea, which does not possess nuclear weapons, it holds great significance in establishing a "deterrent force equivalent to nuclear weapons with conventional arms."
• Korea Tactical Surface-to-Surface Missile (KTSSM):
  • Alongside Hyunmoo-5, KTSSM is a key asset for targeting underground facilities, boasting high accuracy and the ability to penetrate dozens of meters underground to devastate tunnels with its thermobaric warhead.
  • It is being modified for deployment on the Chunmoo multiple rocket launcher and has high export potential.

3. Israel (Israel)

Israel maintains a strong military to counter threats from surrounding countries, but it is assessed to have limitations in developing its own large-scale bunker busters. However, it appears to receive support for U.S. bunker busters when needed, or operates its own medium to small penetrating bombs through its close alliance with the United States.

• Operation of US-made Bunker Busters: It is highly likely that Israel has acquired and operates penetrating bombs such as the U.S.'s GBU-28 or BLU-109.
  • The BLU-109, with a warhead weighing around 870 kg, has been assessed as insufficient to destroy deeply buried nuclear facilities. Some analyses suggested that the BLU-109 could not be used to strike Iran's Fordow nuclear facility.
• Precision Strike Capability: Israel has a track record of effectively striking underground targets, such as Hezbollah's underground hideouts, based on its excellent reconnaissance, targeting capabilities, and precision-guided weapon operation. It has sometimes used tactics of dropping over 100 bombs at 2-second intervals to devastate targets.
• Limitations of Independent Development: Ultra-large bunker busters like the GBU-57 are extremely limited in terms of capable aircraft and incur enormous development and maintenance costs. Therefore, it is difficult for medium-sized countries like Israel to possess them independently. This is why missile-based bunker busters like South Korea's Hyunmoo-5 could be an interesting alternative for Israel.

Conclusion

Bunker busters are essential strategic weapons in modern warfare for neutralizing critical enemy underground facilities. The United States possesses overwhelming capabilities with ultra-large air-dropped bunker busters like the GBU-57 MOP, which, combined with the B-2 stealth bomber, provides the ability to strike underground targets anywhere in the world.

South Korea, aiming to build a nuclear deterrent without nuclear weapons, has developed its own surface-to-surface ballistic missile-based bunker busters like the Hyunmoo-5, achieving world-class technical capabilities in underground bunker destruction.

Israel, either with U.S. support or by utilizing its own medium to small penetrating bombs, manages threats to underground targets based on its sophisticated intelligence and precision strike capabilities. Thus, each country acquires and develops bunker buster capabilities tailored to its security environment and technological level.