The Continuing Ascendancy of English

The International Herald Tribune has been running a series (latest installment here, with links to previous articles) on the rise of English worldwide. It is pretty obvious to me that the number of speakers of English is for the foreseeable future going to rise, because the world needs a standard language and the marginal cost of English is smaller, given the number of people who already speak it. This is not an issue of replacing other languages, but of having a common backup language for all to communicate in. The use of English as the world's common tongue explains, among other things, why Americans and the British lag so badly in learning other languages; the marginal value of mastering another one, given the extent to which English can already be used to communicate, doesn't justify the marginal cost.

I bring it up because the series confirms most of the points I made awhile back in Some Economics of Language, which drew some vigorous dissent in the comments section.