In this video (below), my grandmother, Betsy Hanak, talks about her father (my great-grandfather), Theodore Eickhoff, who was an engineer who designed the Thompson submachine gun (a.k.a. the "Tommy Gun"). He worked under Colonel Thompson, and their team had good intentions for soldiers during World War I when making this gun. Unfortunately, it ended up being a gangster icon in the 1920's. It was finally used for what it was intended for in World War II, which likely pleased my great-grandfather. My grandma also mentioned that she had a chance to fire the gun when she was younger... I sure would've loved to see that!