So you’d be kewl with it if she were 12? Eight? Six?
If you agree we need to draw the line somewhere, then we don’t have a disagreement in principle, just in deciding where to draw a line. I think 14 is too young. She may not enjoy what you dismiss as “middle American lifestyle”, but I want her to have a chance to make a choice when she’s old enough to give informed consent.
Case-by-case basis. Not all 14-year-olds are created equal. To be clear here, I'm not talking about the legalities, but rather my sense of whether or not the the precious little snowflake is the "victim" here or in this particular case is engaged in consensual relations. How do you know that she isn't old enough to have informed consent?