"But an "emotional plea" based speech that encourages resistance in this particular climate, can be interpreted by a segment of the population (left or right) as a call to violent action..."
Can be? How can you say that when that 'emotional plea' fits the literal definition of 'violence'. To wit :
"noun vi·o·lence ?v?-l?n(t)s , ?v?-?- the use of physical force so as to injure, abuse, damage, or destroy"
What Maxine Waters did was call for people who hold positions counter to her to be assaulted. There is no room for interpretation - she did it. There is video evidence she did it.
One need not strike another to be found guilty of the crime of assault. Assault is the mere threat of violence, backed with the reasonable ability to carry out the threat. Therefore, someone who approaches another while they are eating dinner and begins screaming at them is, in fact, guilty of the crime of assault. It is the threat of violence backed by a physical presence. That is what Maxine Waters did - encouraged the assault of those who disagree with one politically. There is no other way to interpret that, unless one is being dishonest.