This is really the first use of x-rays without some kind of medical benefit. And across the whole population.
That's not exactly accurate:
In the late 1940's and early 1950's, the shoe-fitting x-ray unit was a common shoe store sales promotion device and nearly all stores had one.
Nothing is easier than to denounce the evildoer; nothing is more difficult than to understand him. - Fyodor Dostoevski