Sometimes I think I just submit poems to American magazines via Submittable, the portal which many magazines use for receiving work, just to get my reject rate up. I've had very few acceptances via Submittable in general, but of the six over the last 4 years, half are from American magazines, the other half are international magazines. I don't seem to appeal to American writers, even the ones I approach via email. Of the nine acceptances I've had so far this year, one has been via Submittable and I think it was the only American one, the others have been from Europe.
I was brought up in America, studied literature in America and started writing my poetry there, but it seems I can't write poetry that American publishers like. I wonder if I write in a British or Scottish style or if it is like my accent, a hybrid of the three with a dash of that foreign flavour that can't be pinned down.
There are lots of styles of poetry in both groups, many poetic 'schools', but I've never been able to categorise the differences between British and American poetry. I could Google of course, find articles to give me ideas, but I'm not sure how up-to-date they will be and it is a more organic thing, I believe. There's the language, of course, I can hear America in so many American poets' poems, the casual, loose sound of the language. It's not that British poetry is more stiff and formal, but there is a feel to American poetry that I can't emulate or properly explain. And, of course, I'm generalising from the smattering of American poetry I read in magazines and here and there.
I'm sure my references and experiences do separate me from the American reading audience, they are often British, European or specifically Scottish and Finnish. Having to explain the Finnish culture is often hard work, but I don't look at the British-isms I use, beyond language, just basic references that might be putting off or confusing an American reader.
But in the end it comes down to the editors and their preferences. Their education and their experiences will lead them to choose poems that speak to them and this will lean heavily towards other American writers though I'm sure they don't not choose poems because of where the author is from. They will, I believe, have an unconscious preference towards writers who speak of things they can relate to, in styles they like and possible write in themselves. I'm not saying poetry editors don't like to step outside of the box, choose poems that challenge them and their readers, I'm sure many do. But it is harder to be accepted when you are seen as difficult or different.
I must admit I do send to more British magazines overall as I do find I get more work accepted there, but also I feel more at home among those names I recognise. I'll continue to submit to American magazines, just on the off-chance. I do have poems based in America that might appeal more, but I won't restrict myself to just sending them.