Pro and anti-Trump rallies in downtown berkeley, CA, erupted into violence in an event bound to raise serious questions about both president Trump and the political climate that could develop if such confrontations become common. AP reported the incident as it developed at 2:45 PM California time. Thirteen arrests were reported. Later the total was set at 21. There were reports of injuries and bloodied faces.

Nonviolent protests

Not since the volatile days of the Vietnam War has the country been witness to the protests against a President. Such protests against Trump are now common across the country.

They have been remarkable for their nonviolent temperament.

In Berkeley, the situation was complicated by the presence of a pro-Trump group at close quarters. The proper role of law enforcement in such a situation is to separate the groups. Allowing them to tangle and then intervening is is practically an invitation to violence.

Is Trump a provocateur?

Those who have followed Trump from the beginning of his political career remember him at rallies encouraging violence, The power he has as president to shape news virtually guarantees that whatever spin he puts on today's action may be a provocation. Lately, however, there have been signs that Trump is veering toward a moderation of his rhetoric.

If he calls for peace and nonviolence as presidents are expected to do in such a volatile environment, it may be welcomed as a growth in maturity.

The worst case

The worst case would be if Trump himself feels cornered by incessant inquiries about his Russian connections, which appear to be real, and possible defeats of his agenda in Congress, to encourage such incidents.

He has already begun what seems like the creation of a domestic federal police operation in relationship to deportations. The road that this speculation opens is not one anyone wants to go down. But Trump's behavior in the past suggests that painting opponents in false and provocative ways is his natural way of relating to his base.

Today's Clash

AP reported that some 200 people were gathered at Berkeley's Martin Luther King Jr. Civic Center Park. People began pushing each other. Police in riot gear moved in. There were some fistfights and some were arrested. Demonstrators moved into the streets, followed by police.

Last month there was a more volatile protest outside Berkeley's student union, forcing cancellation of an appearance a former Breitbart provocateur named Milo Yiannopoulos.

The latest

The full extent of today's demonstrations and clashes is not yet in. But if we know anything by now, the results will be broadcast in the coming days.