From The Economist:
IS AMERICA RUINING English or giving it new life? Most of this old transatlantic debate concerns words. Is elevator an improvement on lift? Why say transportation when transport will do? Sometimes it involves spelling, specifically the American reforms that made British centre into American center. Pragmatic change or dumbing down? And, of course, the quickest way to tell a Yank from a Brit is by pronunciation.
But the differences between British and American English go beyond words, sounds and spelling to grammar itself. Here they can be subtle, but they are many: the index of the “Cambridge Grammar of the English Language” mentions regional differences in 95 places. America being the parvenu, most people assume that any variations between the two countries result from American innovation, to the (sometimes mock) horror of Britons. In reality, America has often been the conservative one, and Britain the innovator. When British speakers borrow American habits, they are sometimes unwittingly readopting an older version of their language.
The subjunctive had also been on its way out in America, but started to reappear in the mid-to-late 19th century, as Lynne Murphy, a linguist, recounts in “The Prodigal Tongue”. No one knows why; theories include greater Bible reading (which would have kept Americans acquainted with older grammar) and immigrants who spoke subjunctive-filled languages. Whatever the reason, the subjunctive stuck out as a Yankeeism, irking British commentators such as Kingsley Amis, a novelist: “Be careful with any American writings, which often indulge in subjunctive forms.”
. . . .
Stereotypes often have a grain of truth. Americans have indeed innovated extensively with English, as with other things. But language never sits still: the British variety itself went on changing after 1776, as all living languages must. Americans, for their part, eagerly import fashionable British slang. Instead of bemoaning new-fangled Americanisms, British observers could spare a thank you to the old colonies for keeping traditional English safe.
Link to the rest at The Economist
If you would like more about the “subjunctive mood” you can check out a Wikipedia article on the topic. PG didn’t know that verbs had moods, but, as he considers it, why should they not?