"If there were still active shooters out there, he would not have come," said Nancy McFadden, a top aide to the governor.
Brown delayed his trip by a day to travel to San Bernardino for a meeting with law enforcement officials. He arrived in Paris on Saturday, where he's scheduled to participate in nearly two dozen events related to the United Nations summit on climate change.
"It's an important topic, this is an important forum," Brown said in an interview. "California has a role to play, and I wanted to make sure I did that."
He continued, "At the same time, I don't want to minimize the significance of this terrorist attack."
In his most extensive comments yet on the case, the governor said the attack was a "very clear indication that this is a global phenomenon, and that people who are committed to this jihadist doctrine are going to be killing people in very unexpected places. So as I've said, we have to be on guard, and we have to do whatever we can do. And I'm going to be spending some time making sure that our federal-state collaboration really is working and that our own threat-assessment centers are adequately staffed and led to get the job done."
Some California lawmakers have called for tightening the state's already strict gun laws, something Brown has been skeptical of in the past.
"I'll take a look," the governor said. "There have been many bills on this topic, and I'm sure there will be a lot more."
Although the attackers in San Bernardino purchased at least some of their weapons legally in California, Brown expressed concern about looser gun laws in neighboring states.
"Nevada and Arizona are wide open," he said. "So that's a gigantic backdoor through which any terrorist can walk."
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