Tens of thousands of passengers are now bringing "emotional support animals" on airliners each year, where they may ride (for free) in the main cabin, outside any sort of travel case. All the owner needs, according to the New York Times, is a note from a doctor.
I don't fly enough to know how this is shaking out — in part because I find flying these days a major pain — but the potential for conflict seems a clear and, the Times says, growing problem. I am not here to parse the pros and cons, or the relative weight of anybody's rights. But I am here to draw the line, and I draw it here: