The Rise of the Red Star
When the United Nations expanded their power and influence as a central government presiding over other governments, it wasn't just the governments that joined that drew notice, but the ones that did not. The Democratic People's Republic of Korea, in their refusal to be acquired by the UN, found new ways to increase their power on the world's stage. As the UN's stifling and burdensome oversight hindered scientific exploration and created stagnation in scientific progress, North Korea pulled their own "Operation Paperclip," seducing many of the top scientific minds of the world to defect to the DPRK. The promise was that scientists would be granted near unlimited freedom in their scientific endeavors (granted, the end products would be used to benefit the DPRK). A luxurious lifestyle was also promised. Thus, the world suffered "brain drain" and the DPRK skyrocketed in technological power.
Unsurprisingly, the UN increased their pressure on the DPRK and funded propaganda campaigns against the rogue nation, labeling them "a terrorist state" and "a threat to the world," most of which was based on grievances and crimes against humanity not unknown to the world for the past hundred years. Naturally, as a pariah nation, they sought to do business and partner with other pariah nations that shared their resistance ideals - A sort of "Anti-Comintern Pact" of their own. Nova Zion became one of their primary focuses for partnership. Starting with the purchasing of Nova Zion's rockhoppers, the DPRK expanded their presence in outer space. The DPRK not only took interest in Nova Zion's space traveling vessels, but also became keenly aware of Nova Zion's other highly prohibited combat technology, the symphony fighters. Without making their intention completely clear to Nova Zion, the DPRK sought the partnership partly as a precedent to new stage for the DPRK's global authoritative positioning and to acquire symphony fighters of their own.
In the series
In Episode 2 of Symphony Fighters!, the DPRK meets with Gomez to discuss further purchases of rockhoppers and inquires as to whether the rockhoppers can be modified with combat capabilities. Gomez pauses at the thought of arming the North Koreans for space combat. Their meeting is cut short by the interruption of an invading Prosecutor, however they reach out to Gomez again by the end of the Episode.