New Delhi, July 20 -- TAIPEI - At the Democratic Progressive Party's annual convention on Sunday, Taiwan's President Lai Ching-te told delegates that no external force, and no political accommodation, would be permitted to transform their island into "China's Taiwan." The declaration came with Washington simultaneously warning Taipei against any formal move toward independence.

"We must work together to protect our democratic and free way of life, and absolutely never allow 'democratic Taiwan' to turn back and become 'China's Taiwan,'" Lai said at the convention, his most explicit public articulation yet of where he considers the line to lie between political realism and democratic identity.

Taiwan is already an independent country, Lai...