Key point: A second Korean War would kill millions and would best be avoided. However, if a war had to be fought, it would be better if America and South Korea had the best equipment and defenses.

The U.S. Army has maintained a continuous presence in South Korea from 1945 to the present day. Today, the Army permanently bases air defense, artillery, aviation and support units in South Korea, plus a heavy-armor brigade combat team that rotates from the continental United States. In the event of war, it flow even more personnel and equipment into the theater to deal with contingencies of invasion, regime collapse and weapons of mass destruction. Here are five weapons the U.S. Army will need if the balloon goes up again in Korea.

Theater High Altitude Air Defense (THAAD)

THAAD is capable of downing short- and medium-range ballistic missiles, of which North Korea has hundreds, from the short-ranged Hwasong-6 and -7 ballistic missiles to the medium-range Nodong. THAAD will be invaluable to protecting key military, economic and political targets in South Korea, particularly those ports and airfields vital for reinforcing U.S. forces in Korea.

Currently, the United States operates one battery of six THAAD launchers, for a total of forty-eight missiles in South Korea, along with a AN/TPY-2 ballistic-missile defense radar. In a crisis, the United States would likely deploy even more THAAD batteries across Asia, including to fill gaps in coverage over South Korea. (South Korea’s capital Seoul, incredibly, is not protected by the current THAAD deployment.)

The Patriot Missile

Originally developed to shoot down aircraft, the Patriot air-defense missile system has forked into two separate weapons, one to shoot down conventional air threats and the other to shoot down ballistic-missile warheads. Together, the two provide all-around protection from virtually all aerial threats—even drones.

Patriot PAC-2 is the more familiar version of Patriot. PAC-2 is designed to take down anything with wings, from aircraft to cruise missiles. It has some capability against ballistic missiles, but is not the ideal engagement platform for an incoming Scud or No Dong missile. PAC-2 has a range of forty-three miles.

While THAAD takes on high-altitude ballistic-missile threats, the Patriot missile system takes over where THAAD leaves off. The PAC-3 variant, designed for ballistic-missile defense of specific targets such as cities, airfields and headquarters, can intercept incoming missile warheads that THAAD fails to take out. The system has a range of just twelve miles, but a PAC-3 battery launcher can carry sixteen of the smaller missiles as opposed to the four in a PAC-2 launcher.

The M1A2 Abrams Tank

The U.S. Army’s premier main battle tank since the 1980s, the Abrams has been gradually updated in almost all areas, from main gun size to a new digital communications suite. The U.S. Army maintains three combined arms battalions in South Korea equipped with approximately eighty-four M1A2s at any given time.

In a wartime scenario, the Abrams tank will be useful in fending off North Korea’s largely obsolete tank force, which, although numerically superior, has few if any means of inflicting damage on an Abrams tank. Alternately, they could be used to punch a hole in DPRK defenses to spearhead a drive on Pyongyang. Both the U.S. Army and U.S. Marines would use their own versions of the Abrams tank on a Korean battlefield.

M93A1 NBC Reconnaissance Vehicle

The U.S. Army has de-emphasized chemical warfare in recent years, but a conflict on the Korean Peninsula could cause protection against chemical agents to become one of the service’s top priorities. North Korea maintains an estimated 2,500 to five thousand tons of riot, choking, blood, blister and nerve agents. The use of VX nerve agent to assassinate ruler Kim Jong-un’s half-brother Kim Jong-nam in Malaysia suggests the regime would readily use chemical weapons if it they promised a decisive battlefield advantage.

The M93A1 Fox NBC reconnaissance vehicle is based on the German Army Fuchs wheeled armored personnel carrier. The Fox has a crew of three and is equipped with the M21 remote-sensing chemical-agent alarm, M22 automatic chemical-agent detector/alarm, MM1 mobile mass spectrometer for detection and identification of chemical agents, and improved chemical agent monitor (ICAM). The Fox is also equipped with the AN/VDR-2 radiation detector and dosimeter to measure nuclear radiation, possibly emitted from a “dirty bomb” or nuclear explosion.

Mine-Resistant Armor Protection (MRAP) Vehicles

Developed during the 2000s to protect U.S. military personnel from the dangers of improvised explosive devices, MRAPs saved scores if not hundreds of lives by deflecting explosions away from military personnel riding in them. In one of the great unsung military-procurement accomplishments in recent years, the United States procured twenty-four thousand of the tall, ungainly vehicles for duty in Afghanistan and Iraq.

If war breaks out in Korea, they may be needed again. While the American and South Korean armed forces can defeat their North Korean counterparts in any stand-up fight, there is a distinct possibility any conventional war could devolve to an unconventional one if Kim isn’t quickly neutralized. Troops loyal to the regime could easily take their weapons to the hills and start a guerrilla war in support of a hidden Kim Jong-un, planning to bleed the occupiers until they give up and go home. U.S. and South Korean forces will need MRAPs to traverse North Korea’s rugged terrain, rooting out insurgents and escorting supply convoys.

Kyle Mizokami is a defense and national-security writer based in San Francisco who has appeared in the Diplomat, Foreign Policy, War is Boring and the Daily Beast. In 2009 he cofounded the defense and security blog Japan Security Watch. You can follow him on Twitter: @KyleMizokami. This first appeared in 2017.

Image: Reuters.