Kazuhiro Nogi/AFP/Getty Images(WASHINGTON) — Tensions between the U.S. and North Korea reached their highest point in years over the course of this summer, and they don’t look as if they will diminish anytime soon.

Increased missile tests by the North Koreans and a change in approach by the Trump administration have taken the two countries’ leaders into uncharted territory.

The war of words between North Korean leader Kim Jong Un and President Donald Trump further escalated Tuesday when Trump, in his first speech before the United Nations General Assembly, slammed Kim, saying, “Rocket Man is on a suicide mission for himself and for his regime.”

Though much about the so-called Hermit Kingdom’s inner workings remain a mystery, more and more information about its military programs and arsenal is becoming clear. Ahead, what we know about the North Korean threat.

The North Korean mindset

Steve Ganyard, an ABC News contributor and a former deputy assistant secretary of state, was quick to note that nobody really knows what motivates Kim, but “the consensus in the intelligence community is that he’s trying to use nuclear weapons for regime stability and the ability to make the U.S. think twice about whether they would trade Seoul for Seattle.”

Scott Snyder, a senior fellow for Korea studies at the Council on Foreign Relations, agreed that maintaining stability is a major goal, as is projecting a strong image globally and at home.

“I believe Kim Jong Un knows that he’s weak and vulnerable, and he believes that having nuclear capabilities and an ability to strike the United States will help to remove the vulnerability he feels,” Snyder told ABC News.

Snyder also believes that the country’s nuclear arsenal helps bolster his legitimacy domestically.

“Having nuclear weapons has become a key to his survival in sustaining his rule, because he looks around the neighborhood and the world and sees that he’s weak,” Snyder said.

He said that while North Koreans call the country’s nuclear weapons program “the treasured sword,” Kim sees it as “the great equalizer.”

In a statement after the country’s most recent missile test, Kim said “he was seeking equilibrium with the U.S.,” Snyder said.

“In that statement, he’s showing his concern about North Korea’s vulnerability,” Snyder added.

There may be a more tangible goal as well, Ganyard said.

“I think there’s also a growing sense with many people that his ultimate goal is a reunification of the Korean Peninsula under his control,” Ganyard said. “That’s even more scary, because that’s a very offensive mindset that he thinks he can keep the U.S. at bay and that he can defeat the South militarily. Now, that’s highly, highly unlikely, but history is replete with conflicts that have been started by miscalculations.”

Missile launches

North Korea has conducted 14 ballistic missile tests so far this year.

The first came in February, when the North launched a solid-fuel, intermediate-range missile that traveled 310 miles into the Sea of Japan.

Gen. John Hyten, the commander of U.S. Strategic Command, told a congressional panel in early April that the February launch marked a significant advancement for North Korea because it was its first successful solid-fueled missile fired from a mobile launcher, which makes those missiles harder to track because they can be positioned and fired on short notice.

Subsequent missiles have flown increasing distances, reaching more than 600 miles in one March test of a medium-range Scud-er (extended range).

There was a series of missiles that failed before reaching greater distances, but their capabilities reached new heights on July 4. That was when North Korea launched, for the first time, a two-stage intercontinental ballistic missile to mark the United States’ Independence Day.

The missile was launched into a high-altitude trajectory, reaching 1,730 miles up and about 577 miles horizontally, landing in the Sea of Japan. Three weeks later, another ICBM was launched and went even farther.

The latest missile was launched on Sept. 14, and Japanese broadcaster NHK reported that the missile traveled as high as 478 miles and reached a distance of about 2,300 miles.

According to the South Korean Joint Chiefs of Staff, if angled correctly, that ICBM could potentially travel as far as New York or Washington, D.C.

Nuclear arsenal

North Korea has a small arsenal of nuclear weapons, the existence of which have been proven by the country’s five nuclear tests. A 2016 Congressional Research Service report estimated that North Korea has between 66 and 88 pounds of separated plutonium, enough for at least half a dozen nuclear weapons.

U.S. intelligence agencies believe that North Korea now has an arsenal of as many as 60 nuclear devices.

North Korea is currently working toward its stated goal of placing a nuclear warhead on an intercontinental ballistic missile capable of reaching the United States.

U.S. intelligence agencies have also concluded that North Korea tested a hydrogen bomb on September 4, according to a U.S. official.

Military technology

Ganyard said North Korea would have to have four essentials in place before being able to strike the U.S. with a nuclear weapon: the weapon itself, missiles capable of carrying it, technology that allows the missiles to re-enter the earth’s atmosphere without igniting, and the capability to target missiles.

Kim “showed us that the rocket has the range” necessary to strike “most” of the U.S. through recent missile tests, Ganyard said. A U.S. Defense Intelligence Agency report and a recent missile test in which Kim detonated a thermonuclear weapon 20 times as powerful as the bomb dropped on Hiroshima have led officials to believe the country possesses a nuclear weapon that could be placed on a missile.

Whether Kim has the missile re-entry technology and missile-targeting capabilities necessary for such an attack remains a mystery. Ganyard said it’s “still doubtful” that North Korean forces have the re-entry technology needed to have a nuclear weapon explode at its most destructive state. A recent missile test also appeared to show that the bomb that they had tested “disintegrated before fully re-entering,” Ganyard said.

The North’s ability to target missiles remains totally unknown.

“We have no idea where he stands on that technology,” Ganyard said.

Just what kind of re-entry and targeting technology North Korea has is a question that has been unanswered since August.

“Even with the [Defense Intelligence Agency] report out there, I would still say that they have an unproven capability to deliver because there has not been a judgment yet about their ability to master re-entry to the earth’s atmosphere, so that applies for now to the continental United States,” Snyder told ABC News in August. And that still holds true today.

What the recent thermonuclear test has shown, Snyder said, is that the North has nuclear capabilities.

“More importantly, the size of the yield was large enough that it reduces the need for accuracy in the event that North Korea wants to strike a location in the United States,” Snyder said this week.

Snyder also warned that North Korea’s re-entry abilities could change in the coming months.

U.S. defense systems

U.S. troops are permanently stationed in South Korea as part of the security commitment America made to South Korea after the Korean War. In addition to those 28,500 American troops in South Korea, there are also 54,000 American troops stationed in Japan.

Beyond simple manpower, the United States has a layered missile defense system designed to track and intercept missiles launched from North Korea.

It includes missile interceptors aboard Navy ships in the Pacific and large ground-based interceptors located in Alaska and California. However, the viability of the large interceptors has been routinely questioned since they became operational nearly a decade ago.

In late May, the Missile Defense Agency successfully tested an interceptor that targeted an ICBM test missile fired from Kwajalein Atoll in the South Pacific.

The Terminal High Altitude Area Defense (THAAD) system is a missile defense shield designed to intercept short-, medium- and intermediate-range missiles.

In April, the United States deployed THAAD to South Korea for the first time, a long-planned move agreed to last summer after a series of 2016 North Korean missile tests. The United States has also placed the THAAD system in Guam, which could be reached by some of North Korea’s long-range missiles.

Shifts in rhetoric

The overtly aggressive rhetoric that Trump has been using toward North Korea, coupled with the country’s increasing number of missile tests, has brought the question of what happens next to the fore.

While that answer remains unclear, Snyder suggests that the tests are tied to the rhetoric.

Since taking office, Trump has called North Korea a “rogue nation,” a “great threat,” “hostile and dangerous,” “looking for trouble” and “behaving very badly.” In August, he said that if North Korea didn’t stop threatening the U.S., it would be met with “fire and fury like the world has never seen.” Most recently, he has taken to referring to Kim as “Rocket Man.”

Those comments coincide with an increase in tests, Synder said.

“The North Koreans have been pretty consistent in playing tit for tat and responding to threats of pressure with threats of pressure,” Snyder said.

“Within the past months, the escalation in rhetoric has been on the U.S. side — not to point any fingers — and the North Koreans have responded in kind,” he added.

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