Prior to teaching, he was an Army Captain during the Vietnam War; after that, he practiced law on Wall Street with Milbank, Tweed, Hadley & McCloy.
Soderquist was a Fulbright Scholar at Moscow State University during the Cold War.
Other military positions include serving as chief intelligence officer on a General's staff.
Soderquist also penned two mystery novels outside of his academic work: The Labcoat (1998) and The Iraqi Provocation (2003).
On July 3, 2005, Soderquist was in a serious car accident and died from his injuries the next month, aged 61.