I agree that power was the real motivation behind lynchings. The culture that embraced the ignorance of this mob mentality is surprising , but even more than that it is horrifying. It goes contrary to the idea that "We hold these truths to be self-evident..."
There is only one message sent with by a 'lynching'...POWER. With all due respect to Ida B. Wells, the reason behind a lynching might be as sexual just as it could be political or anything else. However, to instill fear was the greatest goal of those seeking to terrorize those who were disenfranchised by decades of racism. Lynchings reached their climax between the mid 20's and 30's, however, the motives remained consistent....in order to retain power, a white man had to re-enforce the pseudo-idea that he was somehow more righteous than a black man just because 'that's the way it is' mentality. This warped sense of reality was permeated into the 1960's, brought to the nation's attention when three Civil Rights workers went missing and were later found murdered in Mississippi. The reason they were murdered...registering African Americans to vote. Finally in the light of sanity and in the wake of these kinds of atrocities, the Federal government passed the 1964 Civil Rights Act and the 1965 Voting Rights Act.
I would have to say that the whole idea of lynching was and is controversial. Most of the time it was done by a group or mob of people and carried out without the benefit of a trial to determine guilt.
I guess the most surprising and controversial aspect of lynching (aside from the horror of the idea at all) is how long it was able to take place without serious, concerted action on the part of individuals, churches or government to combat it. Even into the 1950s and 60s (and some would say, until today) it happened way too often, and there were cases where it was never reported, the person never found, and the record never kept. So we will never know for sure how many victims there were, and to my knowledge, no exhaustive study has been undertaken to identify as many of those victims as possible, so they could be more individually remembered.
While some southerners were guilty of this awful practice of murder, the rest of the South, the rest of society at large, was complicit in their silence and apathy.
To me, the most interesting aspect of lynching is what it said about the sexual fears of white men (and women?) in the South.
Wells, for example, talked about how most lynchings were not really about rape, but that this was used as the most common explanation for the practice. I think it would be interesting to think about what that says about white southern men -- about their own thoughts and fears and about the thoughts and fears of whatever audience they were trying to reach with their rape claims.