And just three months ago, Kim struck a similarly sunny note in his new year's address, speaking of 2016 as a "golden age" during which North Korea would build "a thriving nation."
But in wake of new economic sanctions imposed after its recent nuclear test, Kim's regime seems to be changing its tune. This week, an official mouthpiece of the North Korean state made what appears to be the country's first acknowledgment that it is preparing for worsening economic conditions.
"We may have to go on an arduous march, a time when we will again have to eat the roots of grass," said an editorial in the Rodong Sinmun, the official newspaper of the ruling Workers' Party of Korea.
The sanctions, which on paper are the most severe in 20 years, were approved by the U.N. Security Council after Pyongyang's February nuclear weapons test and more recent long-range missile launch, actions banned by Security Council resolutions.
The sanctions are aimed at further restricting North Korea's international trade and making it harder for the already cash-strapped country to make the money it needs to fund weapons programs. They go as far as to prohibit U.N. members from importing coal and iron from North Korea, two key exports for the reclusive state.
For decades, North Koreans have lived in poor conditions while their government has poured huge sums into weapons development, and the state has used the language of collective sacrifice when selling tough times to the populace.
"It's an old pattern of telling the population to endure short-term hardship for the promise of larger benefits over the long term," Daniel Pinkston, a lecturer at Troy University in Seoul, said of the Rodong Sinmun editorial.
"They're betting that the harm of the sanctions won't last and ultimately their nuclear weapons will make the country stronger," Pinkston added.
The phrase “arduous march” is an allusion to the North Korean state’s claim that its founding leader,
It is now used as a euphemism for the famine that ravaged North Korea in the 1990s, after the country was hit by the loss of economic aid after the Soviet Union's collapse. Things got worse in subsequent years when torrential rains wiped out crops, causing widespread starvation. North Koreans were told to struggle on, calling on the example of the fight Kim Il Sung led for Korean independence in the 1930s against the more numerous and better equipped Japanese.
The regime could be invoking this history to prime the populace for the Party Congress, which will be held in May for the first time in 35 years. At the Congress, Kim could announce changes in the ranks of the country's leadership, and new policy directives.
Paik Hak-soon, an analyst at the Sejong Institute, a think tank near Seoul, said the editorial was "meant to mobilize people both materially and ideologically ahead of the Party Congress, which comes at a time when North Korea is facing both economic difficulties and tensions with South Korea and the U.S."
Tensions have been high between the Koreas lately, with the U.S. and South Korea carrying out annual joint military exercises. This year's are the biggest ever, a fact that has not gone unnoticed by Pyongyang. North Korea launched short-range projectiles off its east coast on Tuesday, the South Korean military reported, one of several such launches in recent weeks apparently aimed at signaling Pyongyang's objection to the drills.
South Korea recently cut off economic cooperation with North Korea, shuttering a joint industrial park along the border.
FOR THE RECORD
March 31, 6:11 a.m.: An earlier version of this article stated that North Korea shuttered an industrial park jointly run with South Korea. South Korean officials closed the facility.
The North Korean economy is in far better shape today than when famine hit in the 1990s, but Kim Jong Un hasn't ushered in an era of prosperity as he pledged, analysts say.
"For the economy, Kim Jong Un's tenure has been a mixed bag," said Benjamin Katzeff Silberstein, a nonresident Kelly Fellow at the Pacific Forum Center for Strategic & International Studies. "On the one hand, he has shown a sense of pragmatism in acknowledging North Korea's problems. On the other hand, no fundamental systemic changes have occurred."
Kim took small steps toward addressing the problem of North Korea's mostly state-planned economy by introducing agricultural reforms that allow some farmers to sell their surplus products, but such measures have not been widely implemented.
Silberstein also pointed out that Kim has been well aware of the need to keep North Korea's elite content, by focusing on improving conditions in the capital Pyongyang and splurging on prestige projects like a luxury ski resort and water park. But with these projects concentrated in Pyongyang, they do little to improve the lives of the majority, the people who are being called on to tighten their belts.
Borowiec is a special correspondent.