In the last five years, North Korea has test fired more than 50 ballistic missiles in an effort to perfect a technology that its opponents fear might someday deliver a nuclear weapon.
So the launch of a missile on Sunday that soared 300 miles across North Korea from west to east before crashing harmlessly into the Sea of Japan might have been another of those tests.
Or it could have been a test of President Trump.
The reclusive country's leader, Kim Jong Un, didn't detail his government's motives for launching the missile — the first such test since before last year's U.S. presidential election. State media on Monday morning characterized it as successful. North Korea watchers suggested several possible reasons for the timing, both practical and geopolitical.
The regime has made missile technology — especially a long-range missile capable of reaching other continents — a national priority, and the test could have been a logical extension of that effort. The launch might also have been an attempt to discern how the Trump administration, which is still formulating its North Korean strategy after visits to Japan and South Korea last week by Defense Secretary James Mattis, might react.
It's possible, too, that the launch was set to coincide with the birthday of Kim Jong Il, the current leader's late father.
"A test like this serves all three purposes at once," said Sheena Chestnut Greitens, a political science professor at the University of Missouri and a senior fellow at the Brookings Institution's Center for East Asia Policy Studies.
Regardless of motive, the action drew strong rebukes from South Korea and Japan as another violation of United Nations Security Council resolutions. Those rules are aimed, in part, at curbing the rogue state's nuclear weapons development.
U.S. military officials said the missile never posed a threat to North America, and the test hasn't yet prompted a strong response from President Trump, who coincidentally was hosting the Japanese prime minister, Shinzo Abe, for the weekend at his resort in Florida.
But Abe called the test "absolutely intolerable." Japan's capital, Tokyo, is about 800 miles from Pyongyang.
"North Korea must fully comply with the relevant U.N. Security Council resolutions," he said at a news conference in Palm Springs, Fla., with Trump standing beside him.
After Abe spoke, Trump said "the United States of America stands behind Japan, its great ally, 100%." He didn't take questions or speak specifically about the test, however. He has said, though, that North Korea is a top priority for his administration.
Officials in South Korea, whose capital is within range of such a missile, condemned what they called the "irrational nature" of the action.
"It is also a grave threat to the peace and security of the Korean peninsula and the international community as a whole," according to a statement issued by the South Korean Foreign Affairs Ministry.
North Korean state media reported Monday that Kim personally oversaw the missile test. The news agency said the missile was a new Pukguksong-2 and was capable of carrying a nuclear warhead. North Korean scientists set the launch angle to avoid violating neighboring countries' airspace, according to the report.
Military leaders in South Korea said they believe the North is seeking to draw attention to its advancing nuclear capabilities and to counter what was seen as a strong commitment to the U.S.-South Korean alliance, as demonstrated by Mattis' recent visit.
On that trip, Mattis reaffirmed the policy of extended deterrence — America's commitment to defend South Korea from both nuclear and conventional attacks. He said any nuclear attack by North Korea would be met with an American response that was "effective and overwhelming."
John Delury, an associate professor at Seoul's Yonsei University, said it's possible the North chose to perform the test as a reminder of its presence, after the Mattis trip and news about Abe's American visit and apparently positive discussions between Trump and Chinese President Xi Jinping.
"This is the only way North Korea can get on the radar," he said. "It's their way of reminding everyone that they are still here."
Some experts had been expecting a missile launch. Duyeon Kim, a Seoul-based researcher at Georgetown University's Institute of the Study of Diplomacy, said it's plausible Kim wanted to test Trump. She said Pyongyang could also just be pursuing its national objective of improving its missiles.
"But what is certain is that the North gains knowledge and comes closer to perfecting its missile technology after each test," she said.
The test firing comes weeks after Kim gave a televised address announcing that his country was close to being able to deploy an intercontinental ballistic missile — a type that in theory could reach the American mainland. The country has numerous missiles, some of them mobile and with modified Russian technology.
A day later, Trump took to Twitter, announcing, "It won't happen!"
Trump's confidence was met with skepticism from North Korea security analysts, who noted that the issue has long confounded the international community — and that Trump hasn't detailed a strategy for dealing with the North.
Despite the United Nations restrictions, Kim's regime has escalated its missile and nuclear programs. He has ordered at least 50 missile tests since he took office five years ago, including as many as 24 last year alone. He has also presided over three nuclear tests — two of which were in 2016.
Just how to deal with North Korea's military threats has befuddled at least three presidents.
President Clinton sought a deal with Pyongyang that ultimately fell apart. President George W. Bush famously lumped the country into his "axis of evil" after the 9/11 terrorist attacks and set tough conditions on any dialogue. And President Obama used a policy that's been defined as "strategic patience," during which the North's missile and nuclear systems continued to advance.
Bush and Obama also relied on a host of sanctions imposed by the United States and the international community. But the country's nuclear program, and the Kim dynasty, have proved resilient.
Most North Korean security watchers now believe the country has enough nuclear material to have created as many as 12 bombs, with some estimates as high as 60.
That leaves Trump with few good options, perhaps even fewer than previous presidents. Among them: persuading North Korea that its nuclear program threatens the Pyongyang regime's survival. There's also the possibility of a negotiated agreement involving regional countries — and perhaps increased economic and political pressure from China and Russia.
One American response has been the Terminal High Altitude Area Defense system, a defense array designed to shoot down missiles. Mattis and South Korean leaders agreed during a recent summit in Seoul to deploy the system here this year.
That system is controversial in South Korea, and it's possible that a change in political leadership in Seoul could seek to reverse that deployment. A new presidential election could occur this summer to replace the country's president, Park Geun-hye, who faces removal from office amid a corruption scandal.
Observers such as Delury still believe diplomacy is possible. He said the North hasn't tested a long-range missile — the kind that might cause a serious international crisis or even military confrontation by the new administration.
"This just kind of rattles the cage a little," he said. "I don't think it forecloses the possibility of some kind of diplomacy."
Stiles is a special correspondent.
4:55 p.m.: Updates with North Korean media calling test successful and describing missile.