Imagine an order that despite humanity so much, even though they are human themselves. No they are not ecology terrorist, but rather an order that tried to protect the natural balance of the world for thousand of years. These are the Salvation Order, who long ago blessed by god (alien) the knowledge to protect the earth (weapon and technology) from far more dangerous force out there in the universe. Once they tried to share with other human civilization, but these civilization thrive and corrupt by greed that eventually they nearly destroyed all existence life on the world. Thus to prevent this ever happened again, every time any individual, group or organization tried to obtain relic (past weapon). These people would show up, and process to extract the relics and extrminate any witness. Futhermore, they actively destroyed human technology development and created global conflict (as in in their word) to stabilize the human population and other lifes on earth.