Even when English dialects (and New England ones, as their non-rhoticism, I believe, is to do with their historical closer affiliation with Britain) lost final -r, they kept it before an initial vowel in the next words. So in "my car isn't working", the -r in "car" will be pronounced; this avoids hiatus. This then spread to words that didn't originally have -r at the end: when "law" sounds exactly the same as "lore", it seems odd to insert an -r into one of them and not the other. Remember, spoken language is of primary importance. The BBC is a last bastion of resistance against this: it issues papers to its newsreaders admonishing them against pronouncing "law and order" as "Laura Norder", but everyone else in the non-rhotic parts of the country does precisely this. Do Bostonians pronounce "my career is..." with an /r/, or not? I'd be quite surprised (and interested) if not. Conversely, do they pronounce "Korea" with an /r/ when a vowel doesn't follow? I'd be surprised if they do. But you're the American, so you'd know; it's a little while since I went to Bwostin, and I didn't talk to any natives for that long.
Yours, Tim .
You must chop down the tallest tree in the forest with... a herring!
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