Kim Jong Un's new 'monster' ICBM could pack a punch, but only if it survives long enough for North Korea to use it

• On Saturday, for the first time in nearly three years, North Korea rolled out a new intercontinental ballistic missile.
• The weapon is an even larger liquid-fueled ICBM than the two ICBM types tested in 2017, but it has yet to be tested and analysts are trying to figure out why North Korea built it.
• Large liquid-propellant missiles like the new ICBM can throw more weight, such as larger or multiple warheads, greater distances, but they are not particularly survivable.
• Weapon experts told Insider that North Korea may be intending to employ a riskier but more survivable approach to deploying and operating this new missile.

Kim Jong Un has a huge new intercontinental ballistic missile that he showed off at a military parade over the weekend, and it could offer North Korea some valuable capabilities, assuming the weapon actually survives long enough to matter.

North Korea test-fired its first ICBM, the Hwasong-14, twice in July 2017. In November that year, it test-fired the larger Hwasong-15.

Analysts argued that these road-mobile, liquid-fueled missiles significantly bolstered North Korea's long-range strike capabilities and nuclear deterrence, assessing that the Hwasong-14 could reach the West Coast while the bigger Hwasong-15 could theoretically range all of the continental US.

This past Saturday, for the first time in three years, North Korea unveiled a new ICBM, one analysts say looks to be among the largest road-mobile, liquid-fueled missiles in the world. Melissa Hanham, deputy director of Open Nuclear Network, called the missile a "monster."

As for why North Korea decided to build a new, even larger liquid-fueled missile, Hanham told Insider that it is a question that "a lot of us are scratching our heads over."

The large size of the new missile offers the possibility of a larger warhead with a higher explosive yield, increasing destructive power and reducing demands for increased accuracy. It also opens the door to multiple warheads, with which North Korea could try to overwhelm US missile defense systems.

But these improved capabilities only really matter if it survives long enough for the North Koreans to get it in the air.

If you are trying to build a survivable road-mobile ICBM force, then solid-propellant missiles are definitely the preferred choice, as both Russia and China have demonstrated in the development of their respective arsenals.

With solid-fueled missiles, "you do not have to pre-fuel the missiles before you use them. You don't generate a bunch of satellite signatures by having support assets. Overall, it's just much safer to operate," Ankit Panda, the Stanton senior fellow in the Nuclear Policy Program at the Carnegie Endowment for International Peace, told Insider.

Liquid-fueled "missiles use hypergolic propellants that explode spontaneously if the oxidizer and fuel make contact, so dealing with that in a crisis, when crews are potentially agitated, is something that most nuclear states just don't want to deal with," Panda said.

While solid-fueled missiles could be rolled out and fired with little to no warning, a large liquid-fueled missile like North Korea's new missile would require more preparation and a lot more time exposed to threats.

For North Korea to safely deploy and operate its big liquid-propellant missile, which is carried on a very large 11-axle transporter erector launcher, it would need the support of additional military personnel, fuel trucks, and possibly even a crane to assist with erecting the missile, Hanham said.

All that equipment and personnel would create a "very big visible signature" for anyone looking for the missile, Hanham added.

Once erected, fueling the missile could take hours. "That is a huge window for preemption with conventional long-range strike capabilities the US would have available," Panda said.

The main advantage offered by a liquid-fueled missile is that you can throw more weight, such as larger or multiple warheads, farther, but it comes at the cost of increased vulnerability.

"The missile offers the opportunity to launch multiple warheads and possibly penetration aids to the US mainland," Hanham said. "The trade-off is that the missile is easier to track and easier to strike preemptively."

"If I were Kim Jong Un, I think I would be pretty happy with the Hwasong-15. I would not invest more in liquid missiles," Xu Tianran, an Open Nuclear Network analyst, told Insider. But because they did build another such missile, it indicates they may have a working concept of operations in mind.

There is a more survivable, albeit significantly riskier, deployment option for the missiles that North Korea might be considering — horizontal fueling with a rollout-to-launch model.

The new missile "may or may not have the capability to be fueled horizontally," a possibility that can't be ruled out at this time, Xu said.

China stores its older liquid-fueled DF-4 ICBMs — which entered service in the 1970s and appear similar in size to North Korea's new ICBM — in tunnels under mountains around the country. Were China to launch them, it would roll them out, erect them, and fire them just outside the tunnels.

North Korea could take a similar approach but instead fuel them horizontally before erecting them, assuming doing so would not put too much stress on the frame, experts said.

"From a safety perspective, it is undesirable to fuel your missile before you erect it," Hanham said, "but it's something the North Koreans might choose to do to increase the speed with which they might launch."

"It is not a perfect concept of operations, but you can imagine them taking certain risks," Jeffrey Lewis, the director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies at the Middlebury Institute of International Studies, told Insider.

"Things don't have to be perfect" to be effective, Lewis said.

During its military parade over the weekend, North Korea displayed four new ICBMs, indicating it could build more if it decided to do so. It could then scatter its arsenal across the country. At that point, the question is whether the US could find them all in time.

"If even one of these things gets through, that is a really spectacularly bad day for the United States, and I think that's the level at which deterrence is operating," Lewis said. "I think the value of this system is that it exists."

The new ICBM is also, Panda said, a "reminder that the North Koreans continue to qualitatively refine their missile capabilities," despite efforts to curb their progress.

And just because North Korea has not displayed a solid-fueled ICBM does not mean it is not working on one.

"Don't fall into the trap of believing North Korea's arsenal only reflects what they've shown us in parades," Lewis said. "I think there are a lot of capabilities that North Korea has that they just haven't shown."