In recent years, underground settings are becoming increasingly relevant to global security and safety. Factors such as rising populations and urbanization are requiring military and civilian first responders to perform their duties in below-ground conditions, in human-made tunnels, underground urban spaces, and natural cave networks. Underground environments can be very dangerous for miners and explorers, as was highlighted by the recent rescue of a Thai soccer team trapped far inside a cave complex for several days. The mission to rescue them was an extraordinary international operation with hundreds of cave and rescue experts and military personnel from several different countries, including the United States, pitching in. Rescue divers first delivered food and medical supplies, and then an air tube to the boys to make sure they had enough oxygen to breathe. They then escorted them out of the cave on stretchers guided by expert divers, one by one.
Criminals, terrorists and military have been using tunnels since long time to evade detection as surface based detection methods are ineffective underground . There has been an explosion of underground warfare in the last five years. From sophisticated cross-border Hezbollah attack tunnels discovered in northern Israel to defensive tunnels that criss-cross the urban battlefields of Syria, Iraq and the Philippines, a tactic familiar to history buffs has emerged as a characteristic of modern war.
Meanwhile, drug cartels are using tunnels to smuggle contraband into the United States from Mexico. Sixty-seven of them were discovered from fiscal years 2011 through 2016, according to the Government Accountability Office. The tunnel threat is a serious and growing concern to U.S and Mexico, as they enable human trafficking and smuggling of drugs and weapons across the border. Recently a drug smuggling tunnel was discovered along the California-Mexico border that set the record for the longest cross-border tunnel ever discovered in Southern California. Around 170 tunnels have been discovered since 1990, Sixty percent of them discovered in just the last three years. According to the Department of Justice’s accounting, the tunnel was estimated to span 800 yards, and likely a lot longer due to its “zig-zagging” route, as Assistant U.S. Attorney Timothy Salel put it. “It is equipped with rail and ventilation systems, lights and a sophisticated large elevator leading from the tunnel into a closet inside the Tijuana residence,” he added. “It is one of the narrowest tunnels found to date, with a diameter of just three feet for most of the length of the passageway.”
Militaries have been engaged in Tunnel warfare or war being conducted in tunnels and other underground cavities. It often includes the construction of underground facilities (mining or undermining) in order to attack or defend, and the use of existing natural caves and artificial underground facilities for military purposes. Militaries and terrorists have been using tunnels to undermine fortifications and slip into enemy territory for a surprise attack, on the other hand also using them to strengthen a defence by creating the possibility of ambush, counterattack and the ability to transfer troops from one portion of the battleground to another unseen and protected. Also, tunnels can serve as shelter for combatants and non-combatants from enemy attack.
Students at Georgetown University discovered thousands of miles of tunnels dug by the Second Artillery Corps, a secretive branch of the Chinese military in charge of protecting and deploying its ballistic missiles and nuclear warheads after translating hundreds of documents, combing through satellite imagery, restricted Chinese military documents and waded through hundreds of gigabytes of online data . The Chinese have called it their “Underground Great Wall” — a vast network of tunnels designed to hide their country’s increasingly sophisticated missile and nuclear arsenal.
The US Navy has built a new $294 million underground nuclear weapons storage complex at the Strategic Weapons Facility Pacific (SWFPAC), a high-security base in Washington that stores and maintains the Trident II ballistic missiles and their nuclear warheads for the strategic submarine fleet operating in the Pacific Ocean. A 16,000-m2 [180,000 square feet] multi-level, underground, hardened, blast-resistant, reinforced concrete structure, with approximate dimensions of 110 meters long by 82 meters wide. Two tunnels (approximately 122 meters long, 6 meters wide, and 6 meters tall) will provide heavy vehicle access to and from the LAPSC.
Pakistan has constructed numerous tunnels to store its nuclear weapons. Such underground facilities can be safeguarded through various means such as blocking their view, controlling access and detecting intrusions. However, most modern air forces possess bombs called earth penetrators that can be used to destroy such vaults. Pakistan has made these tunnels almost impenetrable. An analysis of satellite images taken from 2009 to 3 June 2017 reveals how Pakistan has made special efforts to make its tunnels at Kirana Hills in Punjab province bomb-proof.
India is looking towards towards a stronger option for better connectivity along the entire Line of Actual Control. This is underground tunnels with India planning to construct 17 along the LAC, while developing its capabilities in this regard. Tunnels unlike roads will ensure that the distance to the LAC is drastically reduced and there is all-weather connectivity. This will lead to troops and adequate supplies- even during heavy snowfall that block important roads quickly reaching strategic locations.
Combat capabilities developers have been looking into a wide range of technologies to assist soldiers with maintaining awareness of what’s going on underground. Much of this equipment is very specialized, including seismic sensors, buried fiber-optic cables to monitor acoustic energy, and magnetic-field regulators. Hopefully soldiers will be equipped with such equipment in future (although it’s important to note that each of these technologies has its own weight, costs, and time considerations). But even without these or other new tools this much is clear: they must look down. If soldiers add the underground to their situational awareness, whether they are conducting offensive or defensive operations, it will drive new tactics, techniques, and procedures, as well as new equipment requirements.
In April 2017, the U.S. military dropped the most powerful non-nuclear bomb ever used in combat on a tunnel complex in Afghanistan’s Nangarhar province. The airstrike targeted the Islamic State’s Khorasan branch. The use of the GBU-43/B Massive Ordnance Air Blast weapon, the so-called “Mother of All Bombs,” highlighted the growing threat posed by adversaries’ underground structures. Gen. John Nicholson, commander of U.S. Forces-Afghanistan, cited the challenge of dealing with subterranean targets to justify the use of the bomb, also known as the MOAB. “As ISIS-K’s losses have mounted, they are using [improvised explosive devices], bunkers and tunnels to thicken their defense,” he said in a statement released after the attack. Additionally, hostile regimes such as North Korea are believed to be hiding WMD technology and other weaponry in underground facilities that the U.S. military might need to locate.
Group of scholars and practitioners recently gathered at the Interdisciplinary Center Herzliya in Israel for the first Subterranean Challenges in War and Peace conference and the inaugural meeting of the International Working Group on Subterranean Warfare. One of the many characteristics of subterranean warfare discussed at the conference stood out in particular—the use of tunnel bombs.
Tunnel bombs—or tunnel-borne improvised explosives devices (TBIEDs), to borrow from the nomenclature used to describe the many manifestations of improvised explosive devices—are exactly what they sound like: tunnels dug under enemy forces or fortifications for the purpose of blowing them up from underneath. And when executed effectively, the results can be devastating.
After World War I, the use of tunnel bombs decreased but did not disappear. They were used by terrorists to attack Israel Defense Forces stationed in Gaza until 2005. In 2001, a tunnel bomb was detonated under an IDF base, and in 2004 a thousand-foot tunnel packed with over seven hundred pounds of explosives detonated under an IDF outpost, killing one soldier and injuring five others.The most prominent recent example tunnel bombs’ return is in Iraq and Syria. According to the Department of Defense’s Joint IED Defeat Organization (now the Joint Improvised-Threat Defeat Organization), tunnel bombs were employed forty-five times in 2014–2015.
Many tunnel bomb attacks were recorded, with the videos released for propaganda purposes. These videos showed the world how rudimentary tactics, historically employed at the edge of cities and fortifications or on the European battlefields of World War I, have migrated to heavily populated urban areas and are now found under city streets and buildings. On May 8, 2014, anti-government forces filled a 350-foot tunnel with explosives and detonated them under a Syrian military headquarters that had been placed in a hotel in the middle of the city of Aleppo, killing several dozen soldiers. It took only thirty-three days to dig the tunnel using just hand tools. Just six days later, another tunnel bomb was used, this one almost three thousand feet long and filled with sixty tons of explosives, under a Syrian military checkpoint in the northwestern province of Idlib, killing twenty soldiers. That tunnel took only fifty days to dig. A week later, another massive tunnel bomb exploded in Aleppo killing nearly forty Syrian soldiers.