Since I posted this question, here's my answer. Ultimately, it was watching a cartoon mouse named Hashimoto-San, sometime around 1960:
http://www.youtube.com/watch?v=oiMTeJ7Y ... DA214110A8By today's standards, this cartoon might seem somewhat offensive. But it was important when it was created and shown on CBS less than 15 years after the end of WW2. There were a handful of these cartoons created by Japanese animator Bob Kuwahara. I was 3 or 4 years old at the time, and this immediately created for me an interest in Japan, which led to reading Zen books later on.
When I originally posted this question, I was thinking about karma, and about how an unlikely string of events can pull one through life, from one thing to another. Today I wonder how many younger Buddhists in the west could, ultimately, trace their beginnings in the Dharma back to Teenage Mutant Ninja Turtles.
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