Do we add ability modifier to unarmed strike despite no damage roll?

@dpnorton Do we add ability modifier to unarmed strike despite no damage roll? What if the modifier is negative? #dnd #question Yes, you add your Str. mod. to the damage of a regular unarmed strike. If the modifier is negative, the strike deals no damage.

— Jeremy Crawford (@JeremyECrawford) November 13, 2014