After a months-long pause in its intercontinental ballistic missile tests, North Korea on Nov. 28 conducted the maiden launch of the Hwasong 15 — an ICBM that state media characterized as the rogue nation’s “most powerful” missile yet, topped with a “super-large heavy warhead” and capable of striking the mainland United States. 

Although President Donald Trump had previously pledged to unleash “fire and fury” on North Korea should the regime in Pyongyang continue to advance its ICBM program, his tone was more restrained the day after the new launch. Trump pledged Nov. 29 to impose “additional major sanctions” on the totalitarian state after chatting with Chinese President Xi Jinping, whose government shapes the flow of economic and material aid to Pyongyang.

Trump and North Korean child emperor Kim Jong Un have done this dance before since the reality TV star was sworn in as POTUS, but the new launch poses a major challenge to the Department of Defense. The Hwasong 15 isn’t just an evolutionary leap in first strike capabilities over the Hwasong 14 ICBM that Pyongyang first flaunted on July 4th; it’s apparently terrifying enough to induce Hawaii to resume Cold War-era air raid drills.

So what’s the deal with the Hwasong 15? Here’s what we actually know.

1. The Hwasong 15 is taking North Korea’s ICBM program to new heights… literally.

North Korea state TV claimed on Nov. 28 stated that the ICBM reached an altitude of 4,475 km (2,780 miles) after about 53 minutes of flight, far outstripping the Hwasong 14’s initial altitude of around 2,800 km (1,741 miles) on July 4th and 3,700 km (2,299 miles) during its July 28th test, according to the CSIS Missile Defense Project.

For reference, that’s an altitude 10 times higher than the International Space Station’s, which orbits the planet at around 250 miles. (Nuclear experts tell Task & Purpose that an ICBM fired in anger, as opposed to a showy test, never reaches those altitudes, traveling a much flatter trajectory toward its target.)

What We Know About North Korea’s ‘Most Powerful’ ICBM Yet

The Hwasong 15, North Korea's newest ICBM, in its launch vehicle prior to its test flight on November 28, 2017Photo via KCNA

2. It can reach anywhere in the U.S.

Experts estimate that the older Hwasong 14 could have reached a maximum range of 10,000 km (6213.7 miles) if fired at a precise range-maximizing trajectory — far enough to reach the West Coast or even Chicago, should U.S. missile defenses fail to intercept.

The Hwasong 15, on the other hand, has a potential range of 13,000 km (8,100 miles) “if flown on a standard trajectory rather than this lofted trajectory,” according to an assessment by the Union of Concerned Scientists.

While the Japanese government said on Nov. 28 that the Hwasong 15 traveled only 800 km (500 miles) before splashing down in the Sea of Japan, its projected range means North Korea now has an ICBM with a range that can threaten American metropolises like New York City and Washington — “everywhere in the world, basically,” as Secretary of Defense James Mattis bluntly told media assembled at the White House on Nov. 28.

What We Know About North Korea’s ‘Most Powerful’ ICBM Yet

The estimated ranges of North Korea's various ballistic missiles, excluding the Hwasong 15 ICBM launched on Nov. 28, 2017Photo via Center for Strategic & International Studies

3. Is it nuclear-capable yet? Possibly.

A confidential report by the Defense Intelligence Agency, obtained and reviewed by the Washington Post in August, suggested that Pyongyang had finally managed to develop a miniaturized nuclear warhead capable of fitting atop a long-range ballistic missile, with Kim Jong Un sitting on a stockpile of several dozen nukes. Then again, the DIA made literally the exact same assessment in 2013, so it’s unclear how good their defense intelligence on the matter really is (sorry, guys!).

Related: US Intelligence: North Korea Finally Has Nukes That Can Fit Onto ICBMs »

According to Reuters, most nuclear experts believe that North Korea “has yet to prove it has mastered all technical hurdles” of miniaturizing a launch-ready nuclear warhead. Even if Pyongyang did manage to perfect the process, there’s still the matter of actually delivering its “heavy warhead” to its destination from an exoatmospheric altitude.

Pyongyang claims the Hwasong 15 reentry vehicle is “impeccable,” but international observers aren’t totally convinced. “It remains unclear how heavy a payload the missile was carrying, and if it could carry a large nuclear warhead far enough to strike the United States,” Reuters reports. “It also remains unclear whether the North Koreans have perfected a re-entry vehicle capable of protecting a nuclear warhead during its descent.”

4. Can we defend against it?

Hell yeah, we can! Theoretically, at least. While the maximum range and altitude of the U.S.’s key continental missile defenses, the Ground-based Midcourse Defense (GMD) system, aren’t disclosed by the Pentagon, the U.S. Missile Defense Agency conducted a successful intercept in late May 2017. And with a major influx of funding in the wake of North Korea’s missile tests (to $40 billion in 2017 from $30 billion a decade earlier), the system will hopefully only improve.

But ICBMs may pose a problem for regional partners operating under mobile U.S. missile defense platforms like the Terminal High Altitude Area Defense. The THAAD systems, which the U.S. has deployed in South Korea since May to safely intercept incoming ICBMs, only have a range of 200 km (124 miles), narrowing the window for a successful intercept.

5. Now what?

Well, South Korea is clearly pissed: The military announced that it would conduct a “precision” missile strike in response to Pyongyang’s ICBM test, and the country’s ministry of defense quickly published footage of a salvo of three missiles that lit up the skies above Seoul. Trump, by contrast, had a subdued statement. “I will only tell you we will take care of it,” he told reporters on Nov. 28, calling the new launch a “situation we will handle.”

Their respective reactions are no surprise: The Hwasong 15 wasn’t just North Korea’s 15th missile test of the year, but a clear challenge to the U.S. amid escalating tensions.

“They want us to know they can hit the Eastern Seaboard,” Vipin Narang, a nuclear expert at MIT, tweeted after the launch on Nov. 28. “It’s real folks.”