250-300 words-1 reference within 5 years

Using the Al-Qaeda or ISIS model of influence, these assailants would be considered Home Grown Violent Extremists also known as domestic terrorists.   Are the individuals carrying out the criminal acts simply murderers and not terrorists?  Or is their political messages or forms of demanding political/social change tied to these murders making them domestic terrorists?  Moreover, like Al-Qaeda and ISIS,How have these individuals fostered hate/fear?  Where did it come from?