Nancy Pelosi landed in Taiwan on Tuesday (Aug 2) despite increasing tension between Washington and Beijing. Pelosi was greeted by Taiwan officials as she stepped off the plane around 10:50 p.m. wearing a face mask. The California Democrat, who has a long history of pushing back on China’s human rights record, is the highest ranking American official to visit the self-governing island in a quarter-century.

Pelosi didn’t confirm her travel plans in advance due to safety protocols, but there was much speculation. President Xi Jinping threatened economic and military retaliation if she visited Taiwan. The Chinese president delivered a direct warning to Biden over a lengthy phone conversation they had on July 28. The Chinese leader said, “Those who play with fire will perish by it. It is hoped that the U.S. will be clear-eyed about this. The U.S. should honor the one-China principle.”

Last month, President Joe Biden told reporters that “the military thinks it’s not a good idea right now” for Pelosi to make the trip. Some members of the House are concerned that China will become aggressive towards Taiwan. Director of the Security Studies Program at the Massachusetts Institute of Technology, M. Taylor Fravel tweeted, “The response will almost certainly include a military component, most likely with a show of force in the first instance—live fire exercises, a much greater military presence within the Taiwan Strait and esp across ‘the median line,’ even missile tests.”

Reuters reported several warplanes flew near the median line on Tuesday, and warships have sailed near the line since Monday. China’s Foreign Ministry Spokesman Zhao Lijian said, “A visit to Taiwan by her would constitute a gross interference in China’s internal affairs, seriously undermine China’s sovereignty and territorial integrity, wantonly trample on the one-China principle, greatly threaten peace and stability across the Taiwan Strait, severely undermine China-U.S. relations and lead to a very serious situation and grave consequences.”