Putin has touted an 'invincible' nuclear weapon that really exists — here's how it works and why it deeply worries experts

During Vladimir Putin's annual speech on Thursday, the Russian president played videos that unveiled brand-new nuclear weapons with startling capabilities.

Putin announced an "unstoppable" nuclear-powered "global cruise missile" that has "practically unlimited" range, then showed an animation of the device bobbing and weaving around the globe. He also played a computer animation of a high-speed, nuke-armed submarine drone blowing up ships and coastal targets.

"Russia remained and remains the largest nuclear power. Do not forget, no one really wanted to talk to us. Nobody listened to us," Putin told a crowd in Moscow, according to a translation by Sputnik, a Russian-government-controlled news agency. "Listen now."

David Wright, a physicist and missile expert at the Union of Concerned Scientists, told Business Insider that the idea of an "unstoppable" cruise missile going around the world without being detected is "fiction," since it'd heat up to an extreme degree. (CNN also reported that all tests of the cruise missile ended in crashes.)

But he said that at least one device Putin showed off likely does exist.

"We know they're developing some new systems with a longer range and a larger payload," Wright said.

The known weapon is called the RS-28 Sarmat, though NATO refers to it as the SS-X-30 Satan 2. Russia has been developing it since at least 2009.

Putin showed a video of the Satan 2 during his speech. In it, footage shows an intercontinental ballistic missile launching out of a silo, followed by an animation of it rocketing toward space. The video-game-like graphic follows the ICBM as it sails over a faux Earth in a high arc and opens its nosecone to reveal five nuclear warheads.

Putin claimed this 119-foot-tall missile is "invincible" to missile defense systems.

What makes ICBMs so threatening

Intercontinental ballistic missiles are similar to rockets that shoot satellites and people into orbit, but ICBMs carry warheads and hit targets on Earth.

The missiles travel in a wide arc over Earth, enabling them to strike halfway around the world within an hour. (North Korea recently launched its new ICBM in a high, compact arc to avoid rocketing it over US allies.)

Satan 2, which Putin claimed is already deployed in some missile silos, is a replacement for a 1970s-era Satan ICBM. The new version is slated to reach full service in 50 silos around 2020, according to the Center for Strategic and International Studies.

According to the Center's Missile Defense Project, the Satan 2 "is reported by Russian media as being able to carry 10 large warheads, 16 smaller ones, a combination of warheads and countermeasures, or up to 24 YU-74 hypersonic boost-glide vehicles."

That means one Satan 2 ICBM could pack as much as eight megatons of TNT-equivalent explosive power. That's more than 400 times as strong as either bomb the US dropped on Japan in 1945 — both of which, combined, led to roughly 150,000 casualties.

The technology used to deliver multiple warheads to different targets is called a "multiple independently targetable reentry vehicle," or MIRV. Such devices deploy their warheads after reaching speeds that can exceed 15,000 miles per hour.

Depending on where the warhead is deployed in space and how it maneuvers, each one can strike targets hundreds of miles apart.

Why Putin says the Satan 2 is invincible

A recently demonstrated technology made to neutralize a nuclear warhead is a "kinetic kill vehicle": essentially a large, high-tech bullet launched via missile. The bullets can target a warhead, slam into it mid-flight, and obliterate the weapon.

"But there are a number of different ways to penetrate defenses" like a kill vehicle, Wright said, which may explain Putin's "invincible" claim.

Satan 2 has advanced guidance systems and probably some countermeasures designed to trick anti-missile systems. This might include "a couple dozen very lightweight decoys made to look like the warhead," Wright said, which could result in a kill vehicle targeting the wrong object.

Wright has also studied other methods to sneak past US defenses, including warhead cooling systems that might confuse heat-seeking anti-missile systems, and "disguising a real warhead to make it look different."

But simply deploying large numbers of warheads can be enough: Kill vehicles may not work 50% of the time, based on prior testing, and they're a technology that's been in development for decades.

Yet Satan 2 is not exactly unique.

What the US has that compares

The US in 2005 retired the "Peacekeeper" missile, which was its biggest "MIRV-capable" weapon (meaning it could deploy multiple warheads to different locations).

One Peacekeeper missile could shed up to 10 thermonuclear warheads, each of which had a 50% chance of striking within a roughly football-field-size area.

But the US has other MIRV-capable nuclear weapons in its arsenal today.

One is the Trident II ballistic missile, which gets launched from a submarine and can carry up to a dozen nuclear warheads. Another option is the Minuteman III ICBM, which is silo-launched and can carry three warheads.

Arms control treaties have since reduced the numbers of warheads in these weapons — Trident II's carry up to five, Minuteman III's just one — and retired the Peacekeeper.

Today, there are still about 15,000 nuclear weapons deployed, in storage, or awaiting dismantlement, with more than 90% held by the US and Russia.

Cold War 2.0?

Wright said Putin's recent statements and the similarly heated comments and policy made by President Donald Trump echo rhetoric that fueled nuclear arms build-up during the Cold War era.

"What's discouraging is that, at the end of the Cold War, everyone was trying to de-MIRV" — or reduce the numbers of warheads per missile — he said.

Removing warheads helped calm US-Russia tensions and reduce the risk of preemptive nuclear strikes, either intentional or accidental, Wright said. Russia's move to deploy new weapons with multiple warheads, then, is risky and escalatory.

"One of the reasons you might want to MIRV is if you're facing ballistic missile defenses, and Putin talked about that," Wright said, noting that the US has helped build up European anti-missile defenses in recent years. "The clear response is to upgrade your offensive capabilities."

He added that Russia's move also shouldn't be surprising in the context of history: After George W. Bush withdrew the US from the Antiballistic Missile Treaty in 2001, a Russian general told the New York Times the move "will alter the nature of the international strategic balance in freeing the hands of a series of countries to restart an arms buildup."

The charged statements of President Trump, who has called for a new arms race, have done little to reverse that course.

In fact, the Trump Administration plans to expand a Obama-era nuclear weapons modernization program. Over 30 years, the effort could cost US taxpayers more than $1.7 trillion and introduce smaller "tactical" nuclear weapons that experts fear might make the use of nukes common.

This story was published on March 1, 2018, at 5:59 p.m. ET and has been updated with new information.

Putin has touted an 'invincible' nuclear weapon that really exists — here's how it works and why it deeply worries experts

What makes ICBMs so threatening

Why Putin says the Satan 2 is invincible

What the US has that compares

Cold War 2.0?

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