> This is additionally confounded by the fact that British people really do mean "sarcasm" when they say "irony."
I've never experienced this in actual conversation with British and/or other non-US English speakers. But the internet definitions I'm finding seem to all include 'sarcastic but somewhat subtle' in the definition of ironic. For me the definitions of sarcasm and irony do not intersect. Sarcasm is intentional whereas irony is at best random or more often a signifier of implied 'fate'.
Irony certainly can be random or a signifier of implied fate in the case of literary/dramatic irony.
Verbal irony, which is closely related to but not identical to sarcasm (though there is quite a lot of debate on exactly the relationship among psycholinguists) is most certainly intentional.
"I don't wear my seat belt because if I'm uncomfortable I'll drive more dangerously."
"Sounds like you've really thought that one through."
Verbal irony, possibly sarcasm depending on whose definition you buy, but definitely intentional in any case.
I've never experienced this in actual conversation with British and/or other non-US English speakers. But the internet definitions I'm finding seem to all include 'sarcastic but somewhat subtle' in the definition of ironic. For me the definitions of sarcasm and irony do not intersect. Sarcasm is intentional whereas irony is at best random or more often a signifier of implied 'fate'.