Taiwan's armed forces operate a number of the American-made, surface-to-air and anti-ballistic missile systems, whose sole purpose is to deter and intercept Chinese aircraft and projectiles in the event of a conflict across the Taiwan Strait. The foreign military sale—the first involving Taiwan this year and the second under the Biden administration—will "sustain, maintain, and improve the Patriot Air Defense System," according to DSCA's statement.
The U.S. has no formal diplomatic relations with the democratic island but has been its staunchest international backer for decades, even after Washington and Beijing established official ties in 1979.