I think that explains why we never had a chance. All of our strategies were formed on the one assumption; that we were fighting alien invaders.
By the time of the events in Final Fantasy: The Spirits Within there had been four Phantom Cleansing Missions performed, with the most recent of which was supposedly designed to end the "war" between the Phantoms and humans; occurring near Tucson in 2043.
The missions have proven failures on various levels, with a nationwide draft in the United States enacted to supplement forces lost during those missions. Physical attacks have proven to possess little effect on the Leonid Meteor and the Phantom population overall, resulting in the creation of the Zeus Cannon as an absolute weapon designed to decimate the meteor site.
- Ryan Whittaker's father was part of the ill-fated fourth Phantom Cleansing Mission.
- The design of the soldier uniforms worn in the fourth Phantom Cleansing Mission were actually based on the original concepts for the Deep Eyes uniforms.
- The dead soldier that Aki found in the Tucson Wasteland was one of the inspectors killed by Phantoms in an alternate opening sequence that never made it to film.