China has made the second-largest invasion into Taiwan's air defence zone, with Taipei reporting 30 jets, including more than 20 fighters, entering the territory. Taiwan's defence ministry said late Monday that it had scrambled its own planes and deployed air defence missile systems to keep an eye on China's latest moves.

Beijing has begun sending huge sorties into Taiwan's defence zone in recent years to express unhappiness and to keep Taipei's ageing fighter fleet taxed on a regular basis. Taiwan, which is self-ruled and democratic, is constantly threatened by invasion by China, which regards the island as its own and has threatened to take it by force if necessary.

Last week, the US accused Beijing of inflaming tensions over the island, citing aircraft incursions as an example of "increasingly provocative rhetoric and conduct," according to Secretary of State Antony Blinken. Blinken's comments come after US President Joe Biden appeared to defy decades of US policy when he indicated during a visit to Japan that if Taiwan was invaded by China, Washington would support it militarily.

Fighter jet
Taiwan Air Force's F-16 fighter jets fly during a demonstration at Hualien airbase, eastern TaiwanReuters

The White House, on the other hand, has maintained that its policy of "strategic ambiguity" on whether or not to intervene has not changed. The invasion on Monday was the greatest since a total of 39 planes crossed the air defence identification zone, or ADIZ, on January 23.

The ADIZ is not the same as Taiwan's territorial airspace; it encompasses a much larger area that overlaps with a portion of China's own air defence identification zone and even several mainlands. The jets entered the southern corner of the ADIZ before circling back out, according to a flight map given by the Taiwanese defence ministry.

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The Chinese Air ForceReuters

Regular incursion by the Chinese

Taiwan detected 969 Chinese warplane incursions into the ADIZ last year. On October 4, 2021, China sent the most planes in a single day, with 56. In that month, there were a total of 196 intrusions, most of which occurred around China's annual national day celebrations.

Taiwan has reported 465 invasions so far in 2022, up nearly 50% from the same period last year. The sheer volume of missions has put the air force under a lot of strain, and it's seen a lot of tragic mishaps in recent years.