Korean imperalism?

The Times has this piece on a modern version of mail-order brides, this time being exported from Vietnam to Korea. As someone fascinated by cultural geography ( I warmly recommend Migrations and Cultures by Tom Sowell in this regard), I wonder what is happening to the demographic ratios in Vietnam? Are the Koreans essentially plundering the women of Vietnam? The Times story is silent on this question. Watch out for anti-Korean riots in Hanoi. Aux armes, sex-starved Vietnamese bachelors!