I think it is likely from what I have read that the grand jury made the right decision in this case. However, there is no doubt that America's law enforcement agencies have become far too trigger-happy, with many recent examples of innocent Americans being shot by over-zealous, and even downright sociopathic, police officers (such as the killings of Samantha Ramsay and Keith Vidal or the shooting of Robby Tolan in his parent's driveway or of 70-year-old Bobby Canipe, who was reaching for his walking stick). Many shootings by policemen involve black victims and you have to think the Ferguson protestors have a valid point.
The real cause of the race relations problems in Ferguson and across America is a vast historical legacy of bitterness that isn't easily overcome. For almost two centuries Africans were transported in appalling conditions to serve as slaves in North America and, as if that were not enough of a crime against humanity, their descendants for multiple generations inherited their bondage. Millions of Americans spent their entire lives being owned by another human being. Slavery was finally abolished by President Lincoln's Emancipation Proclamation in 1862, although it took another three years for the Union troops to enforce the proclamation throughout the South by defeating the Confederacy. It has been less than 150 years since then and to appreciate how little historical time that is, consider that there are likely to be people alive today whose grandparents were born into slavery. And, of course, it didn't stop there. Reconstruction after the Civil War led to another century of discriminatory 'Jim Crow' laws in the South that only ended with the Civil Rights Act and other measures in the 1960s. So, the wound is still very raw.
However, much as I sympathise with the historical plight of African-Americans, I don't accept the idea of 'white guilt' as it is contemporarily applied to Americans (or New Zealanders). Americans of European descent today are not responsible for the crimes of their ancestors. Prejudice is about pre-judging people (which is the very root of the word) on the basis of some collective trait, and Americans of European descent should no more be judged by their racial make-up than African-Americans, for to do so would be to pile one wrong on another. People should be judged by their actions as individuals, not tarred by association with the deeds of their forebears. The founding fathers of America got it right when they said that all men are created equal and have unalienable rights. The fact that they did not practice what they preached does not lessen the truth and utility of their famous words today. The answer to America's bitter racial legacy is to reaffirm and hold fast to those great truths.