groupophobia 

fear or intolerance of groups other than one's own

Donald Trump uses paranoia and groupophobia as a means to motivate his followers.

groupophobia by Luke Indago August 6, 2016

groupophilia 

the tendency or urge to be a part of and accepted by a group of people

Since individuals survive best within a group, groupophilia is a potent motivator of human behavior and is the root cause of peer pressure, social conformity, religion, patriotism, and gangs.

groupophilia by Luke Indago August 6, 2016