She is the highest ranking US official to visit there since 1997 with Newt Gingrich. Taiwan claims self-rule on its island since winning a civil war with China back in 1949.
The US maintains informal relations and defence ties with Taiwan that was recognized in the 1979 US Taiwan Relations Act.
China has cut off contact with Taiwan since 2016 when Taiwan’s President refused to endorse the claim from China that both Taiwan and China represent a single Chinese nation.
Military actions on both the US and China side have increased since the announcement of the US dignitary’s visit to the Region.