French revolution started with a riot. While the terror state that came soon after is condemned, it was the violent spark that realized the Enlighment ideals in Europe.

1830 was a riotous year globally. Belgian independence started with a riot, and was successful in a sense, carving out a place for libertarian optimism and industrial expansion from a war-weary continent.

These are both fairly conventional pop-culture interpretations. But maybe similar developments would have happened without the flash in the pan of some undirected mob breaking things.