If the US fought a War on Pedophilia™ as rigorously as they've been fighting their War on Drugs™ for decades, easily 90% or more of the adult male population would end up in prison.

No, we'd just have to cremate the bodies.

the United Nations' definition of "child" is any person under 18.

No shit, Sherlock. The United States doesn't do whatever the UN tells us, though, so many states have an age of consent of sixteen or seventeen — when it really should be eighteen or twenty-one.

And statutory rape is ANY sexual interaction between an adult and a child, regardless of circumstances, intentions, and practices involved.

That's false. Many states have "Romeo and Juliet" laws: exceptions if they're close in age, usually around three years, so an eighteen year-old won't get in trouble for dating a seventeen year-old.

Everything else doesn't matter; pedophilia is pedophilia, and should always be punished with death.