Is there somewhere I can hear the difference? I don’t want to google those particular terms!
What, so you want me to google them!? 
I suppose you could google the American English pronunciation of “corn” or “horn”.
Another one I just remembered: he used to tell me about how lovely it is in “The Algov”. At the time I wasn’t familiar with The Algarve. Good job I looked it up or I would have spent my life pronouncing it “Algov”, which would sound stupid coming from an American.
But there’s no hawn or cawn to contrast them with. I want to know if I can hear the difference or not. Need to find a less rude pair of words.
These alternate spellings are so confusing. Algov would be pronounced completely differently to Algarve in England. I think I pronounce it ‘Algahve’.
Yes, “Algahve” is what it sounds like, and how I should have represented it.
As far as the porn, corn, horn sound . . . I honestly don’t mean to be snarky, but have you really never heard the American pronunciation of these words? We Yanks pronounce the “r”; you Limeys do not. I didn’t usually have any issue with understanding him but neither “porn” nor “pawn” are words that come up often (at least for me).
The link I posted above gives the different pronunciations across the Anglosphere of the word “core”. So, if you assume “cause” does not have such different pronunciations, then that’s the difference right there.
I have to confess though, to my ears the difference seems pretty subtle. It might be one of those language things where if you don’t need to parse those different sounds in daily life, your brain just isn’t tuned to hearing the difference. (I’ve certainly had my fair share of of experiences in China of “Hahaha, you said <blah>, you meant <something that sounds identical to me to blah>!! ROFL”)
Thousands of times, I’m sure. But once you’ve ‘tuned in’ to a particular accent you don’t think about the actual sounds, just what word the person is saying. I think it’s like @Mijin says; if you don’t need to distinguish two sounds then your brain lumps them together and it’s hard to hear a difference.
Also, people with non-rhotic accents don’t think of it as not pronouncing the r. Like in your example, ‘porn’ is not pronounced the same as ‘pon’. The r changes the vowel sound, it’s not just a silent letter. Compare with accents that drop the ‘h’, where it is obvious something is missing or added.
Can you hear the difference between cot and caught? Or Mary, merry and marry?
I can only imagine how much harder that must be in Chinese with all the tones.
No joke. And the British guys are disappointed too, because regardless of pronunciation the standard transliteration of the name is Porn. I mean, their eyes don’t omit the R too, do they?
I don’t understand. Is the joke now that British men would be disappointed too, because the name is both spelled and spoken just like the short form of the word “pornography”? Because that would be the opposite of the original joke.
And in terms of “omitting the R”, let me restate again the difference, AIUI, between British and American English on these phonemes
In British English, the words “porn” and “pawn” are pronounced exactly the same way.
And, furthermore, it’s not like the “r” is silent; it’s coding for a vowel sound, and the word “porn” would not be pronounced the same without it.
In American English, what I learned from this thread, is that “porn” and “pawn” have different vowel sounds. However, it would be wrong to say that the US pronunciation is “really” pronouncing the “r”, as it’s still just functioning here as coding for a vowel sound, it’s not a rhotic consonant.
How about Brits adding an extra ‘r’?
I’m always slightly irritated by ‘drawring’ instead of ‘drawing’, but it seems to be very common in the UK.
I knew a lot of Brits in Thailand, and some definitely pronounced the R in “porn.” Perhaps it depends on regional accent.
Again, “pronouncing the R” is meaningless.
I pronounce the R: I pronounce the words “con” and “corn” very differently, the R is not a silent letter.
The American English pronunciation of “or” is also a vowel sound. It’s no more, or less, “pronouncing the R”.
This is where I’m confused. Perhaps it comes down to the official, technical terms, but “r” is not a consonant? Not challenging you, just trying to understand,
Well, OK, consider the names “Dan” and “Dawn”.
W is a consonant, but no consonant sound has been added in the second name. Instead, W functions together with the A to collectively denote one vowel sound (in IPA terms I think [æ] became [o:], link)
Or heck, consider a word like “though”, where the O, U, G and H are together representing a vowel sound (yes I’m aware “ough” can actually code for a lot of sounds, but regardless, it’s generally coding for one, open-mouth sound). It’s irrelevant that two of those characters are consonants.
It’s the same with “or”, which is two letters together denoting one sound, which happens to be different in British or American English (FYI dialects like Australian, seem to hem more closely to the British on this one).
ETA: “ough” does not only code for single vowel sounds, because, for example, in the word “cough” I think it’s a vowel and a fricative. 
I knew I shouldn’t have brought up “ough”, which is a famously broken part of English spelling…
Thanks for taking the time and being so courteous! I kind of get it. So, the “or” sound in American English is considered a vowel sound, right? The “rrrrr” sound (sorry, I don’t know the correct phrasing) is made with the mouth but we don’t consider the r to be it’s own consonant. I guess my confusion was part about “not pronouncing the r”, as, to my ears we do, but in the language of . . . language, we don’t 
Probably another case of people overcorrecting the pronunciation to match the spelling. See “comfortable,” “often,” and “falcon.”
I found that the Macmillan dictionary features British and American pronunciations of the word extraordinary (see at the bottom to switch the audio pronunciation), and IPA definition.
But, to my ears, the difference remains incredibly subtle, and I find it weird that anyone would consider one reading to be “pronouncing the R” and the other to not be. As I initially said, if any letters are being cut, it’s the first “A”.
Do you mean FALcon or FALLcon? How else have you heard it pronounced?
Wikipedia says ‘rhotic consonants, or “R-like” sounds, are liquid consonants’, and ‘this class of sounds is difficult to characterise phonetically’. So helpful! But it says ‘r’ is a consonant, at any rate.
@Mijin, there are some words where you and I would simply not pronounce the r. Farther, for example, is pronounced the same as father for me, but (most) Americans say them differently. I think the difference in vowels between accents is confusing the issue with porn and pawn.
In the 40s, it was pronounced FAW-con. Listen to Bogart in The Maltese Falcon.
No, this is flat out wrong. The word “corn” has four distinct sounds in rhotic English. Look at how the very British Cambridge Dictionary shows how Americans and Brits pronounce corn:
us /kɔːrn/
uk /kɔːn/
Each symbol (except the “:”) between the slashes represents a distinct sound. Four symbols, four sounds in the US version.That “r” in the pronunciation guide is not there to represent a change in the preceding vowel sound, it is there to represent the true “r” sound, same as the “r” in “run”.