Two Chinese jets crossed into Taiwan’s airspace last month as a warning aimed at the US, ratcheting up tension over a US-China dispute that boils down to their different interpretations of the ‘right of transit passage’ clause in the Law of the Sea

South China Morning Post
Date: 8 Apr, 2019 
By: Mark J. Valencia

Illustration: Craig Stephens

On March 31, two PLA Air Force fighter jets deliberately crossed the median line
of the Taiwan Strait and, despite repeated warnings from Taipei’s military, flew 43 nautical miles into Taiwan’s airspace. This was the first such crossing in nearly two decades.
This latest incident may have been a warning to the Democratic Progressive Party and Tsai Ing-wen government because of increasing US political support in the face of Beijing’s more assertive posture. But it was also probably a manifestation of a creeping clash of positions
between Beijing and the US over the regime for passage of warships and warplanes through the strait. This controversy has potentially dangerous practical implications.
The median line has existed since 1955 when it was declared by General Benjamin Davis, then the commander of the US 13th Air Force based in Taipei, as part of the “rules of engagement”. There was no formal agreement and Beijing has not officially recognised it because, in its view, Taiwan is an inalienable part of its territory. Nevertheless, the median line has in practice served to separate the two sides and their military activities.
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