Gingrich is not without support to his argument. Here is just a partial list of items that the dangerous cocktail of liberalism and violent video games is responsible for over the last 40 years:
Jeopardy!

Dunkaroos
The Oklahoma City bombing
Slap bracelets
Teen pregnancy
AIDS
Autism (specifically asperger's syndrome)
Gigli
Flava Flav
Homosexuality
Rape Culture
The expiration of the Assault Weapons BanBrett Ratner films
Genocide (Darfur, Kosovo, Somalia)
Super Mario Bros. & Duck Hunt
Dick Cheney
Pee Wee Herman
Hostess Cupcakes
Global warming*
The existence of the Middle East
Tom Green
People who aren't white
The Harlem Globetrotters

Harlem
Hummus (not to be confused with HAMAS)
HAMAS
Nuclear weapons
Poverty
Unemployment
Homelessness
Goth Music
*This is a tricky one because although liberalism is responsible for it, according to most conservative experts it doesn't actually exist