Anomie in societies or individuals, is a condition of instability resulting from a breakdown of standards and values or from a lack of purpose or ideals. — Émile Durkheim. 

Professors back from secret missions
Resume their proper eruditions,
    Though some regret it;
They liked their dictaphones a lot,
They met some big wheels, and do not
    Let you forget it. — W. H. Auden

Some Germans were perhaps attracted to the Nazi movement because it gave them a sense of belonging. Membership gave them new importance and the ability to smash social norms.

Seyward Darby claims in “Sisters in Hate,” that “Hate can be understood as a social bond, a complex phenomenon that occurs among people as a means of mattering and belonging.” 

Americans may have joined the Trump movement because it gave them a feeling of importance, a chance to smash norms, and a feeling of belonging. These feelings must be strong enough so what the movement professed didn’t much matter, or more likely resonated with preexisting, perhaps shadowy, beliefs.