I certainly wouldn't wager any money on Chinese being the language to replace English [as a global lingua franca]!
P.S. After thinking about it some more, I would offer the following scenario. Suppose that by the end of the 21st century, the U.S. has declined to a fifth-rate power -- with a Mexican-level economy, Russian-quality highways, and the military might of Sweden. Suppose also that China has risen to become the world's leading military, industrial, and economic superpower.

Under these circumstances, I can see several possibilities for a future "international language of business, science, aviation, etc.":


  1. China pragmatically decides that English is already very well established as a lingua franca, and that there's no need to "re-invent the wheel" -- instead, Chinese businesspeople and scientists continue to learn English as a second language, as they do now.
  2. China decides that it hurts Chinese pride to use the language of Yankee and Limey imperialism, and begins to vigorously and massively promote Esperanto as the new "international language." For Chinese people, Esperanto is "politically neutral", and is also a little bit easier to learn than English; and for non-Chinese, Esperanto is vastly easier to learn than Mandarin! So Chinese support could be the best thing that ever happened to Esperanto.
  3. An entirely new language develops -- some sort of "creolized" hybrid of Chinese and another language could actually succeed as an international lingua franca. (The other language blending with Chinese would most likely be English, but not necessarily.)
  4. Standard Mandarin Chinese becomes the new international language.



Out of these possibilities, I would guess that (4) is by far the LEAST likely to happen, because of the linguistic disadvantages of Chinese that I already mentioned.

And, incidentally, one can add to the list of factors that make Chinese an unlikely candidate as a global "second language." For example, in large American cities like NYC, LA, and Chicago, there are probably more U.S. citizens who are native speakers of Chinese, than there are PRC citizens who are native speakers of English, in all of China. (I would make the same guess about Canada, the UK, and Australia, too -- they all have more native-Chinese-speaking citizens than China has native-English-speaking citizens.) The reason for this has less to do with language, and more to do with Chinese politics and culture. Of course, China could change its naturalization policies to encourage immigration of English speakers, but the cultural barriers would remain.

Somewhat related to this is the point that relatively many Russians, Arabs, Indians, and Brazilians have cousins who are naturalized citizens of the US (or Canada, or the UK, or Australia), but relatively few Russians, Arabs, Indians, and Brazilians have cousins who are naturalized citizens of China.

A final point against Chinese is that many of its nearest Asian neighbors have historic reasons to distrust China, and as much as some of them may grumble about "Anglo-American cultural imperialism", the idea of "Sino-Chinese cultural imperialism" is even MORE unattractive. In other words, the Japanese and South Koreans and Thais and Filipinos would vote (with their wallets) for ESL, but not for Chinese as a Second Language.

I would guess that if English is someday replaced as "the world's favorite second language", Spanish would be a very likely candidate, IF the economies of Latin American countries improve.

Spanish is at least as easy to learn as English (unlike Chinese), and South America has historically been successful at welcoming and assimilating immigrants from different ethnic backgrounds (also unlike Chinese).