As leader Kim Jong Un celebrated his birthday, CNN, the only U.S. broadcaster operating in the country, spoke to North Koreans at the newly-opened Science and Technology Center.
Architecture student Lee Won, visiting the center that is the public face of the government's push to develop its technological and scientific capabilities, said that it was "one of his favorite places."
Asked what he thought of the purported H-bomb test, the 27-year-old said: "I think it is very wonderful, it is a very good result for our country's safety."
"If you are trying to guard your house, you have to take your stick very firmly."
The world has reacted with outrage and skepticism over the purported test, as the U.N. threatens further crippling sanctions.
Situated on the small islet of Ssuk-som, southwest of Pyongyang, the high-tech science park, designed in the shape of an atom, looks out of place in a country where rolling blackouts are the norm.
The center, opened on January 1 by Kim Jong Un, is centered around a replica of the 2012 rocket that launched North Korea's first and only satellite into orbit. Government minders said that the center showed how much of a "priority" science was for the country.
Inside, visitors and workers sat tapping enthusiastically at banks of computers connected to the North Korean intranet, a tightly-regulated facsimile of the World Wide Web that largely consists of educational sites and propaganda.
Another visitor to the center, 22-year-old medical student Lee Jue Sung, said that the nuclear program "is for national defense, to protect our country from our enemy."
"U.S. imperialists always want to invade our country, they are so aggressive," he said.
Requests to speak to scientists involved in the nuclear program itself were denied by North Korean officials. CNN's movements are tightly controlled within the country, and any interviews are dependent on government minders.
CNN's visit took place as South Korea resumed broadcasting propaganda via loudspeakers
over the DMZ -- the heavily guarded and fortified buffer zone between the two Koreas -- an act that has infuriated Pyongyang in the past.
The timing of the broadcasts -- on Kim Jong Un's 33rd birthday -- were particularly "provocative", government minders said.
While Kim's birthday is not officially marked or celebrated, the minder said that "everyone knows whose birthday it is."
Sticking to their guns
When asked about skepticism of whether the H-bomb test was actually successful, North Korean officials were defensive.
The United States, South Korea, Japan and China are testing for airborne or ground radiation in the region, but more than 24 hours after North Korea announced a successful test, the country's closest neighbors say they haven't found any evidence of radiation.
Officials told CNN's Will Ripley that new technology used in the purported test "minimized the amount of radiation that has gone into the surrounding environment."
"They also told us the test was conducted far deeper into the mountain than previous tests," Ripley said.
North Koreans that CNN spoke to were unconcerned by the threat of potential further sanctions, saying that "as a nation they will collectively tighten their belts and continue to grow their missile program."
Doubling down on nuclear
Kim has invested heavily in science and technology, as he pursues his "byungjin" strategy of simultaneous development of nuclear weapons and the economy.
The dictator's late father, Kim Jong Il, spent a huge amount of resources expanding the military, building the country's standing army into the fourth largest in the world, with more than a million soldiers.
This cost the country heavily in terms of resources and empowered the military, which has traditionally supported the Kim regime but some see as a potential threat should the ruling family seem vulnerable.
The purported H-bomb test, as well as previous nuclear tests, "cements (Kim's) authority domestically and his clout internationally," said Mike Chinoy, former CNN International correspondent and the author of "Meltdown: The inside story of the North Korean nuclear crisis
"By developing the nuclear capability, Kim will be able to cut the budget of the conventional military and bring them to heel."
Later this year, Kim will helm the Worker's Party Congress, the first time such a gathering has been held in 35 years, and may represent a realignment of political power away from the military.
A statement carried by KCNA in October highlighted the need to "further strengthen the party... and enhance its leading role."
A birthday present for Kim
There has long been a debate as to how effective external pressure is on North Korea, one of the most sanctioned countries on Earth, and particularly its leadership, which has managed to shield itself to a large degree from the hardship suffered by the general populace.
"This is a regime that let two million of its own people starve to death in the 1990s," said Chinoy.
"They are not going to be bothered if the ordinary people of North Korea suffer because [new] sanctions hurt the economy."
While sanctions may no longer concern officials, one thing that has previously spark anger and consternation in Pyongyang is South Korean propaganda broadcasts piped into the country via huge speakers on the demilitarized zone (DMZ).