By Christopher Woody
The Trump administration wants to have a force ready to fight in the heavens by 2020, but the US Army is already spending a half-billion dollars to prepare for fighting underground.
In a speech at the Pentagon on Thursday, Vice President Mike Pence described a US Space Force as "an idea whose time as come."
"Our Administration will soon take action to implement these recommendations with the objective of establishing the United States Department of the Space Force by 2020," Pence added.
Critics have said a new Space Force is unnecessary, while an argument for it is that rival powers like Russia and China are growing more able to strike at US assets in space and at US assets from space, missions whose importance necessitate its own dedicated command and even military force.
The ultimate structure of the Space Force remains unclear, as does what its responsibilities and resources will be.
Elsewhere in the Pentagon, however, officials are looking in the opposite direction to prepare for the future of warfare.
US Army leaders have said that next war will be fought in mega-cities, and the service has started an effort to train troops to fight not just in but also beneath those environments.
An accelerated effort started in late 2017 will devote about $572 million to train and outfit 26 of the Army's 31 active combat brigades for operations in large-scale subterranean facilities, according to a Military.com report in June.
Teams have been activated to train leaders from each of those brigades to operate in large-scale underground facilities. As of June, five BCTs had been trained, and the trainers had a January deadline to finish training the other 21.
Underground combat will require Army infantry to navigate, communicate, overcome heavy obstacles, and engage enemy forces in facilities that range in size and complexity from relatively small corridors to sprawling subterranean compounds.
"We did recognize, in a megacity that has underground facilities — sewers and subways and some of the things we would encounter ... we have to look at ourselves and say 'OK, how does our current set of equipment and our tactics stack up?'" Col. Townley Hedrick, commandant of the infantry school at the Army's Maneuver Center of Excellence at Fort Benning, Georgia, told Military.com.
"What are the aspects of megacities that we have paid the least attention to lately?" Hedrick said. "And every megacity has got sewers and subways and stuff that you can encounter, so let's brush it up a little bit."
The Army's Asymmetric Warfare Group, which is often asked to assess future threats, has been tasked with developing a training course for underground fighting, relying on modular facilities to simulate such combat.
A portion of the money assigned to the effort will go to acquiring specialized equipment, like radios, breathing systems, or night-vision goggles. An Army source told Military.com that the tactics and techniques of underground fighting are similar to those used to clear buildings, with complicating factors like a lack of light or air.
Underground warfare is nothing new. Special units of US troops, usually engineers, were tasked with exploring tunnels found during the Vietnam War. More recently, US and partner forces have dealt with ISIS fighters operating in underground tunnels in Iraq and Syria.
Villages around Mosul, Iraq's second-largest city, were found to have extensive tunnel networks that were likely used as meeting places and escape routes. In early 2017, the US used its largest nonnuclear bomb, nicknamed the "Mother of All Bombs" against what was said to be a complex of tunnels and caves used by ISIS.
Prior to the wars in Iraq and Afghanistan, dealing with underground structures was largely the responsibility of special-operations units like the Army's Delta Force or Rangers or the Navy's SEAL Team Six.
But Army researchers have said that special-operations forces alone will not be able to deal with the scale of underground combat in a future conflict with a peer or near-peer adversary. One Army source told Military.com that an estimate made in 2017 found about 10,000 large-scale military facilities that could serve as underground cities.
More than 4,800 of those underground facilities are in North Korea, which has used such subterranean structures to house nuclear-weapons facilities and, in case of war, could use them to funnel thousands of troops into South Korea.
Moscow and other major Russian cities are replete with undergound bunkers, tunnels, subway lines, and other facilities, many of which were built during the Cold War.
China, home to dozens of densely populated cities, has a vast network of tunnels and underground facilities used to house its missiles and nuclear arsenal. Iran, too, has used underground complexes for its nuclear program.
"I think that modern warfare and modern combat, [it will] occur mainly in urban areas, and urban areas are a place that tunnels and underground facilities can be used, mainly by asymmetric opponents, as something that changes the equation," Brig. Gen. Nechemya Sokal, chief of staff of the Israel Defense Forces IDF Technology and Logistics Branch, said on the Modern War Institute podcast in early 2017.
Sokal said that Hamas' use of tunnels for variety of operations, including infiltrating Israeli territory, created a number of challenges that required new technology and different tactics to address.
"We have to change our doctrine and the way we do things, because underground facilities are not so intuitive as buildings and places we are used to being," Sokal said.