Before the First Robotech War
He was a supporter of the Anti-Unification League and an acquiantance of T.R. Edwards.
Before the SDF-3 departed from Earth, he was put in charge of the defense of Earth and rebuilding the Robotech Defense Force. Leonard was not optimistic of the mission, feeling that the REF's exit from Earth Defense would leave the Earth vulnerable to attack from any alien forces which chose to attack the planet; Zentraedi or otherwise. He predicted that if the mission went through and the Spacefortress did not return home that war against another alien threat would quickly return to the planet. (Robotech II: The Sentinels) It was a fear which would be proven correct within seven years.
The Second Robotech War
He was the leader of the Southern Cross Army that protected Earth after the SDF-3 parted to Tirol, he was disliked for his "Win-or-Die" mentality that caused the death of many of the Southern Cross soldiers and pilots. During the conflict against the Robotech Masters, he was convinced that the Robotech Masters had to be exterminated in order to win the War.
This led to various internal problems in the Southern Cross where many generals knew that the only way to end the war was by peaceful means. He was in Monument City during the Robotech Masters' final assault on the Southern Cross, where he said that he would stay to the end. Later a Bioroid shot directly at his office, killing him instantly.