Nancy Pelosi, United States Speaker of the House, departed Taiwan on August 3 after a controversial visit to Taiwan. The US has recently been intensifying its encirclement of China, and this visit has been criticized as a deliberate act of provocation intended to bait China into a response.
Explained: Pelosi stirs US-China tensions with Taiwan trip
For China, reaffirming that Taiwan is not a separate country is extremely important given the historic balkanization of the nation by imperialist powers.