"Earth was just a tiny planet hiding in the corner of the universe. But now Earth started moving out into space with massive military strength. [...] Earthlings have drawn the attention of the entire universe. But we must not forget that science should only be used for justice. It should never be used to show off one's power."
- ―Alien Kyuloo, The Sky-Flying Iron Colossus.
At some point after promoting to the rank of a staff officer, Kaji proposed the Friendship Plan to solve the ongoing incidents of alien invasions after suffering a heavy loss from his days as an Ultra Guard officer. Due to its inhuman nature, a portion of TDF voiced their disagreements in this plan, some of them includes Furuhashi (whom Kaji blame for said loss in his past), Shiragane's Ultra Guard, and vocal supporters of Furuhashi. Ironically, Furuhashi's team were sent to explore Planet Valkyrie as part of the Friendship Plan in his retirement day. An infiltrating Alien Valkyrie took notice of the Friendship Plan and instigated the destruction of TDF's Moon Base, pinning the blame of the incident to Furuhashi's supporters after making the incident seemingly an armed coup. Once arriving on Earth through an emergency shuttle, Valkyrie tarnished the Ultra Guard's reputation in the eyes of the public, which ironically pressuring TDF and the general population to further accept the Friendship Plan. By the time Seven arrived on Earth, he was able to destroy Valkyrie once no other remaining host was left. Although UG's reputation was exonerated, Kaji repaid Valkyrie's invasion by bombing the alien's planet as Friendship Plan's first target.
The Friendship Plan continued to destroy more planets despite its inhabitants hardly showing any signs of interest in invading Earth. Planet Earth started to gain notoriety in outer space, and even the Alien Galo decided to use Alien Kyuloo's Daitekkai to start their war against TDF. A year later, a surviving Nonmalt made herself known to Seven and revealed that the Friendship Plan has more sinister plans in behind the scenes. Namely, the supposedly bombed planets were in fact invaded by Kaji's cronies to plant more branches of TDF's base in outer space (hence an invasion on mankind's part) and that the Omega Files contain a secret that Kaji's men try to protect at all costs. After invading TDF's underground base, Seven discovered that Kaji's extremist actions were done in order to hide the fact that mankind's ancestors were invaders themselves, thus should word got out to space civilizations, then mankind are possibly fated to lose their planets. The Ultra Guard nonetheless broadcasted the Omega Files to the outer space while Seven killed Zabangi.
The Friendship Plan was finally put to an end thanks to a revived Furuhashi, but Seven decided to allow himself to be imprisoned in the Horsehead Nebula for his act in meddling with civil wars of Earth natives. Furthermore, a peace treaty was signed by TDF with the other civilizations to prevent subsequent alien invasions in the future. Although peace returned to Earth for five years, Alien Garut's machinations and the infiltration of aliens in TDF effective rendering the peace-treaty as invalid.
- The Friendship Plan is a tribute to the experimental R1 missile that was used to destroy Planet Gyeron as a testing site, which eventually resulted with the attack of Star Bem Gyeron on Earth.
- The Friendship Plan is also a darker take on Kaoru Kiriyama's famous quote of Earth supposedly being defended by mankind alone instead of the Ultras. Ironically, Kiriyama is one of the many casualties of the Friendship Plan, as Kaji's men killed him in order to ensure the existence of the Omega Files as a secret.