There are over 370 "mental disorders" listed in the latest version of the DSM (Diagnostic and Statistical Manual of Mental Disorders.) The list includes "Tobacco Addiction Disorder" among other equally mundane and ridiculous so-called "mental illnesses."
 
If the DSM is the standard by which politicians wishes to remove our rights to own guns, then I'd guess 90% of the American people could probably be classified with a mental disorder of one kind or another.
 
BEWARE, BEWARE