On a March morning in 1945, Linus and Ava Helen Pauling’s young son Peter ran into the house and told his parents, "You’ve got to come out here and look. Someone’s painted stuff on our garage." The Paulings were appalled by what they saw. Someone had defaced their home, scrawling "AMERICANS DIE BUT WE LOVE JAPS" below a crudely drawn Japanese flag. "JAP" was grafittied on their mailbox. When police and reporters arrived, an outraged Pauling told them that the painting was probably a response to the Japanese-American man the Paulings had hired as a gardener for a weekend, a gesture of friendship for a young soldier on his way to report for duty in the Army. Pauling then compared the vandalism, "this un-American act," as he called it, to the persecution of Jews by the Nazis. It was the beginning of a major change in his life. The World War II battle against Japan was still being fought, and many Americans were dying. After the newspaper published his thoughts, the Paulings started to receive hate mail and whispered, anonymous death threats over the phone. The family was frightened. When a local sheriff refused to post an armed guard around his house when Pauling was away, Ava Helen called the local chapter of the ACLU (a group with whom she’d been working in the fight against the internment of Japanese-Americans during the War) and asked for help. ACLU pressure resulted in the posting of a guard, and things soon calmed down.

There were no more incidents. But Pauling was deeply affected by this threat to his family. He was a patriot and a supporter of the US government. He had helped fight against his country’s enemies in World War II by leading research projects to develop better explosives and rocket propellants. But now he had seen a different side of America. Now he had seen intolerance first-hand. He had seen a lawman who had to be forced to uphold the law. He had seen a liberal legal group, the ACLU, successfully spur positive change. His wife Ava Helen had always said that there were pressing issues of social justice in the nation that needed more attention. After the incident Pauling began to listen to her ideas more closely.