With the launch of its latest ballistic missiles this year, North Korea has dragged Japan into its ongoing tussle with South Korea and the United States over the deployment of a US advanced anti-missile shield in the South against the North.
One of two missiles fired on Wednesday landed in waters within Japan's exclusive economic zone, drawing international condemnation and prompting the United Nations Security Council to convene an emergency meeting yesterday.
Analysts see the latest missile test as a show of force against US plans to deploy the Terminal High Altitude Area Defence (Thaad) battery on South Korean soil.
Some also suggest that the North this time round targeted Japan in order to drive a wedge between China and the US' alliances with Japan and South Korea.
Pyongyang and Beijing oppose the Thaad deployment, which Seoul insists is necessary to protect its people against the growing missile threats from the North.
North Korea has launched 32 missiles since its young leader Kim Jong Un assumed power in 2011 - twice the number that was fired during his father's 18-year rule.
The latest missile flew 1,000km and landed in waters just 250km away from Japan. Given its range of up to 1,300km, it could have hit the Japanese mainland.
Mr Shawn Ho, an associate research fellow with the S. Rajaratnam School of International Studies, said North Korea made a "calculated strategic move".
"Japan will now have to respond and this will further bolster the Japan-US alliance which will further irritate China," he said.
He noted too that Pyongyang was well aware that the missile test would become "further justification" for the Thaad deployment. But this too was within its calculation.
"North Korea might thus be deliberately making things even more difficult for China which has all along voiced its strong stance against Thaad. By driving a deeper wedge between China and (the US-South Korea alliance), North Korea might hope to have more 'breathing space' since these countries will be more (focused on) one another and less (on) North Korea directly," he said.
Pyongyang might also be targeting Japan to irritate its eastern neighbour, as Tokyo has been a harsh critic of North Korea.
After Tokyo called North Korea a key threat in its Defence White Paper published on Tuesday, Pyongyang may have found it "rewarding and worthwhile" to test a missile just to ruffle Tokyo's feathers, said Dr Lee Seong Hyon of the Sejong Institute think-tank.
He said Japan also makes for an easy target as it is near enough for North Korea's missiles to reach. And it will give Pyongyang the attention it craves, with Tokyo more than other states viewing North Korea as a threat. South Korea, by contrast, has become immune to the North's behaviour.
Japanese international security expert Tosh Minohara from Kobe University has a more scathing view of the act. "North Korea appears to take the 'I can be really bad if you're not nice to me approach'. So we're dealing with a schoolyard bully," he said.
Pointing to the recklessness of the act, he said the missile could have hit a Japanese fishing boat and "created a diplomatic row".
The root of the North Korean problem is the lack of communication between the country and the outside world, said Dr Lee.
Dealing with North Korea requires a "vigorous carrot and stick strategy", but, so far, the US and South Korea have meted out only punishment and offered no rewards, he added.
North Korea has yet to comment on its latest missile test.
But its KCNA state news agency yesterday cited Mr Kim as saying at a military meeting that it is important to strengthen the army in political, ideological and moral aspects.
