The Economist carries an article about how the practical common tongue of Central Europe evolved from Latin, to old German, to Russian, and is now moving to English. 75% of students are studying it as a second language. This movement in New Europe is reinforcing the trend already found in Old Europe. Russian is the second most popular choice to study in school in the Balkans, but falls in favor as you head south. It is still commonly spoken by the older generation, however. German has apparently not been promoted in those areas invaded during World War II. France is surprisingly popular in Romania, but nowhere else.
(In this situation, I'd wonder whether "English" is here seen as something relating to Great Britain or America, or whether it's seen as relating to Hollywood and world consumer markets... my gut feeling is that students are choosing English because it happens to be the easiest language to use across groups on the internet, but there's nothing in this article to buttress that suspicion of mine. In other words, they're not choosing "english" so much as "the internet's common tongue" of simple unaccented ASCII.)
Whatever, my main driver still applies: When people in every part of the world rely on English as a hub language to reach other cultures, then it's smart for people who have that hub language as their primary language to study reaching out to a wide variety of other cultures... while others study centripetally, we study centrifugally.