Editor's note: Cheng Xiaohe is an associate professor at the School of International Studies at Renmin University of China and a senior researcher at Pangoal Institute. The article reflects the author's opinion, and not necessarily the views of CGTN.

Today marks the 7th anniversary of Kim Jong Il's death. In the past seven years, the changes in the Democratic People's Republic of Korea (DPRK) have been beyond imagination. 

In March 2013, the current DPRK leader adopted the Byungjin policy in an effort to develop the nation's nuclear weapons and economy simultaneously. Since then, the DPRK has conducted three nuclear detonations and numerous missile tests that met strong opposition at the United Nations (UN).

But at the same time, the DPRK has carried out some significant measures to reform its agricultural and industrial sectors. It has set up more than 20 special economic zones in order to attract international investment.

Still, harsh economic sanctions have had a damaging effect on the domestic economy. In addition, as the DPRK's nuclear and missile programs progressed, its economy suffered.

Faced with internal and external challenges, Kim Jong Un, who assumed his father's mantle in 2011, emerged from obscurity and began to gain world attention. In his 2018 New Year speech, Kim made clear his intention to make a comprehensive change both domestically and internationally.

On the once-nonnegotiable nuclear issue, Kim ordered a suspension of nuclear and missile tests and a blow-off of the nuclear test sites. This significant concession was quickly reciprocated by the U.S.-ROK decision to freeze their joint military exercises. The DPRK and the United States thus jump-started negotiations over the DPRK's nuclear and other associated issues.

However, the negotiations seem to have hit a snag not only because of the complexity of the issues, but also because the talks themselves have entered a substantive stage, in which both sides must work out a feasible action plan that requires vigorous implementation.

Even though the twists and turns in the negotiations may become routine, the stalemate is expected to be broken in the second summit between Kim Jong Un and Donald Trump, expected to take place early next year. 

On inter-Korean relations, Kim Jong Un initiated Olympic diplomacy that in turn set inter-Korean rapprochement in motion. After three inter-Korean summits in less than half a year, the two Koreas are stepping up their efforts to put their hard-earned rapprochement on a solid and sustainable track.

In the security field, both sides have taken measures to reduce hostility in the border area. To improve confidence-building in the economic field, they are doing preparatory work with a focus on road and railway cooperation.

Their environment and forestry cooperation also began to take a shape; in the diplomatic field, a joint office, established in Kaesong, helped to facilitate inter-Korean communication; in the social field, family reunions resumed at a quickened pace; and sporting exchanges become regular as both sides jointly prepare to apply to host the 2032 Summer Olympic Games.

However, inter-Korean relations seemingly are hitting a ceiling due to the ongoing sanctions against the DPRK. If two Koreas cannot make any breakthroughs in their economic cooperation, the momentum of their developing relationship will likely be lost. 

On its relations with major powers, the DPRK also has achieved remarkable progress.

Kim Jong Un initiated summit diplomacy by paying his first overseas visit to China and he broke protocol by doing so three times in less than three months. Chinese President Xi Jinping and Kim Jong Un reached a strategic consensus and the two countries fully recovered their political relations.

Kim Jong Un also held a historic meeting with U.S. President Trump in Singapore on June 12, a feat his grandfather and father tried to achieve but failed. The mere meeting between the heads of the perennial adversaries greatly fueled speculation that the DPRK's nuclear issue, the abnormal relationship between the DPRK and the United States and the armistice on the Korean Peninsula could be settled in the not-so-remote future.

The aforementioned changes are significant. The DPRK's leader and people are doing their part to create a favorable condition for big changes inside the country.

Earlier this year, the Third Plenum of the Seventh Workers' Party of Korea Congress adopted two resolutions, announcing that the Byungjin line has accomplished its mission and the DPRK will single-mindedly focus on economic development.

Kim Jong Il once tried to achieve a goal that all the Korean people have dreamed about, namely, being able to “eat rice, drink meat soup, wear silk clothing and live in tiled houses.” His son Kim Jong Un is determined to adopt the right policies to realize his father's unaccomplished mission.

The DPRK will not dogmatically copy China or Vietnam development models, but create its own by borrowing from other countries' experiences and lessons. For now, the country should continue to move forward toward its denuclearization pursuit and seek a complete lifting of the sanctions that cause pain to its economy every day.

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