Interesting debate!
Firstly, my standpoint; I'm English.
For me, there are two seperate things here; one is about the natural evolution of a language. Languages are not owned by any nation or country. And they are subject to a journey of evolution just like anything. As they evolve, their features change. They become more suited to their environment.
I will openly admit that many aspects of American English agitate and annoy me, as a Brit, because the driving force of the evolution of American English seems to be laziness. Dropping letters to save time or effort;
Colour ...... becomes Color.
Or, even worse in my irrational, unreasonable, patrio-egocentric view on this subject, they drop entire words, to save effort;-
"One hundred and forty"......... becomes "One Hundred Forty".
Of course, in reality, this 'laziness' is perfectly reasonable and rational - what is the point or benefit in 'protecting' the old, historical iteration of a language? ... there's none at all is there?
The objective of a language should be nothing other than to aid communicaton as effectively and efficiently as possible. In which case, the evolution of English from British to American persuasions is a natural and reasonable occurance. Laziness = Efficiency!
.......what this is really about for me, is whether or not the English language, and it's place in this debate, is part of the wider discussion around whether the US is taking over the whole globe in terms of cultural invasion, based on economic power. It is a shame to bring mainstream, geo-politics into an otherwise prettier discussion about language but the heart of the debate (in my opinon) lies in whether the demise of orginal English, in favour of US English in a part of the take-over of the world by the US. In England, modern day versions of MS software, does not even have a spellchecker that acknowledges British English any more. The (correctly spelled for us!) word "colour" will now always raise an 'error' and a suggestion to 'correct' the spelling to 'color'.
For me, that is frustrating and annoying!
None of this is squared at individuals from the US, (nations are artificial political boundaries, we're all just people in my eyes), this is a political assertion and view ....... but there is a perhaps reasonable statement that says that the US is absorbing the rest of the world, culturally.