Article continues below advertisementA red line between peaceful protest and escalating unrest came into sharp focus in Los Angeles this weekend, as a massive "No Kings" demonstration ended with dozens of arrests and clashes with law enforcement.Thousands gathered in downtown L.A. as part of a sweeping wave of protests across the U.S. and internationally, aimed at opposing President Donald Trump's policies and the ongoing war in Iran. What began as a largely peaceful march quickly shifted by evening, as tensions rose near a federal detention center.