Apart from being an outburst of violence and anger, what political function does an uprising serve?

Many important changes take place in liberal democracies through massive protest and through the use of the riot. I studied in Germany over the summer and then I traveled around to dozens of cities. All across the nation, documented actions and uprisings were cited as causes of political change during the reign of the closed society. In Leipzig, for example, weekly violent protests convinced the DDR that they needed to become the kind of open society demonstrators envisioned. Same thing all across Eastern Europe.

Even in our own country, race riots led to the civil rights movement; uprisings have prevented massive evictions of poor communities; draft riots sprouted anti-war movements and anti-war movements ended the occupations; the Rodney King uprising brought racial profiling and police brutality to the fore of political debate for a decade. If you are only embarrassed by changes that are taking place in the present, but you revere changes that took place in the past through the same means, then you have to ask yourself whether you are embarrassed by those means or something else.