An event such as the 1992 Los Angeles riots will happen in the United States in the future. It really depends on the situation at hand. Anything is possible because when you upset a lot of Americans at once then they have a right to fight back and get taken seriously.
The Los Angeles riots in 1992 were caused as a result of the Rodney King situation, when police officers were acquitted. Sadly, this type of riot could definitely happen again, and has historically happened more than once. When a large group gets angry and acts out physically rather than through dealing with emotions in a safer manner, riots can break out. When people aren't thinking straight (that includes police and the rioters) and are in the heat of the moment, things just escalate.
The nation is more divided than it ever has been between conservatives and liberals, aside from perhaps the time leading up to the Civil War. The tension is almost palpable, and people who have been feeling oppressed are starting to revolt and stand up to their oppressors. I believe that if things continue down this path, we will be lucky if an event like the LA riots is all that happens.
The 1992 riots were mainly over race relations in the country and what was perceived to be an unfair outcome simply based on race. I think that this is completely possible in today's day and age. Think of the tensions after the Trayvon Martin killing. I think it's very problematic.
I believe events such as the 1992 Los Angeles riots will happen in the United States, in the future. Given all that is wrong with our country: high unemployment rates, lack of equality, income inequality, racial tensions, gender tensions, etc; I believe it is reasonable to assume that these tensions will continue to build, especially when the government does nothing to rectify the problems.