California
Bombardment of Ellwood (Attack on Santa Barbara)
Santa Barbara was a notable port city, and at the time, known for the Ellwood oil field and refinery. It was a tempting target for the Japanese, who were still reeling from their surprise attack at Pearl Harbor. Seven submarines were tasked with patrolling the American west coast during this time. On February 23, 1942, the I-17, commanded by Commander Kozo Nishino, breached off the coast and began firing upon the industrial port, specifically targetting oil tanks. Most of the damage that resulted from the 20-minute attack was felt from the city's pier, but the oil storage tanks remained intact.
In the aftermath of the bombardment, some residents decided to flee the city, fearing that other attacks were imminent. The US government encouraged "blackout" campaigns, much like what the British had done for communities along the coast. It is also believed to have prompted the internment of Japanese-Americans, as that policy would be enacted shortly following this incident.
Some historians speculate that Nishino's choice of target to be made of revenge. A few years before the war broke out, Nishino was a merchant who had previously docked in Santa Barbara. As the story goes, he slipped and fell onto a cactus plant, causing the crowd around him to erupt in laughter.
"Battle of Los Angeles" incident
As news of the attack on Santa Barbara spread, fears rose that the Japanese were going to attempt a Pearl Harbor-esque attack on American cities along the Pacific coast. Cities like Los Angeles and San Francisco were placed on high alert.
This "war nerves" reached its peak when sirens ran, anti-aircraft artillery shot out, and the beams of spotlights bobbled into the sky waiting for an enemy that would never show up. The government would later admit that what triggered the incident may have been a weather or surveillance balloon gone astray, but that wouldn't be announced until 1983.
Some skeptics believe the incident to have been triggered by extra-terrestrials.
Both the "Battle of Los Angeles," the Bombardment of Ellwood, and the associated panic at the time became a major inspiration for the 1979 film 1942.