EXPLAINER: Why is a Pelosi visit to Taiwan causing tension?


              A Cheng Kung class frigate fires an anti air missile as part of a navy demonstration in Taiwan's annual Han Kuang exercises off the island's eastern coast near the city of Yilan, Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and President Tsai Ing-wen on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible visit by U.S. House Speaker Nancy Pelosi.(AP Photo/Huizhong Wu)
            
              A Ching Chiang class patrol ship fires off depth charges underwater as part of a navy demonstration in Taiwan's annual Han Kuang exercises off the island's eastern coast near the city of Yilan, Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Tsai on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (AP Photo/Huizhong Wu)
            
              A S70-C anti-submarine helicopter flies above Taiwan's SS-793 submarine which performed an emergency surfacing as part of a navy demonstration in Taiwan's annual Han Kuang exercises off the island's eastern coast near the city of Yilan, Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Taiwan's President Tsai Ing-wen on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (AP Photo/Huizhong Wu)
            
              A Cheng Kung class frigate fires off chaff, a decoy made of a small cloud of aluminium or plastic, meant to confuse enemy missiles as part of a navy demonstration in Taiwan's annual Han Kuang exercises off the island's eastern coast near the city of Yilan, Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Taiwan's President Tsai Ing-wen on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (AP Photo/Huizhong Wu)
            
              In this photo released by the Taiwan Ministry of National Defense, an AIM-9P4 short range sidewinder air to air missile is fired from a Taiwanese Ching-Kuo Indigenous Defense Fighter during Taiwan's annual Han Kuang exercises in Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Taiwan's President Tsai Ing-wen on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (Taiwan Ministry of National Defense via AP)
            
              In this photo released by the Taiwan Presidential Office, Taiwan's President Tsai Ing-wen, center, poses with for photos with Taiwanese navy personnel during inspection of Taiwan's annual Han Kuang exercises in Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Tsai on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (Shioro Lee/Taiwan Presidential Office via AP)
            
              A Cheng Kung class frigate fires an anti air missile as part of a navy demonstration in Taiwan's annual Han Kuang exercises off the island's eastern coast near the city of Yilan, Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Tsai on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (AP Photo/Huizhong Wu)
            
              A P3C anti-submarine plane flies past the radar tower of a Taiwanese Keelung class destroyer during a patrol as part of the island's annual Han Kuang exercise off the island's eastern coast near the city of Yilan, Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Tsai on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (AP Photo/Huizhong Wu)
            
              In this photo released by the Taiwan Presidential Office, Taiwan's President Tsai Ing-wen is seen through glass onboard a navy ship during inspection of Taiwan's annual Han Kuang exercises in Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Tsai on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (Shioro Lee/Taiwan Presidential Office via AP)
            
              Two Mirage 2000 fly in parallel as they launch several flares as part of Taiwan's annual Han Kuang exercises off the island's eastern coast near the city of Yilan, Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Tsai on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (AP Photo/Huizhong Wu)
            
              A Cheng Kung class frigate fires an anti air missile as part of a navy demonstration in Taiwan's annual Han Kuang exercises off the island's eastern coast near the city of Yilan, Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and Tsai on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible Pelosi visit. (AP Photo/Huizhong Wu)
            In this photo released by the Taiwan Presidential Office, Taiwan navy personnel work on a map during the annual Han Kuang exercises in Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and President Tsai Ing-wen on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible visit by U.S. House Speaker Nancy Pelosi. (Shioro Lee/Taiwan Presidential Office via AP) In this photo released by the Taiwan Presidential Office, Taiwan navy personnel form up on a navy ship during the annual Han Kuang exercises in Taiwan on Tuesday, July 26, 2022. The Taiwanese capital Taipei staged a civil defense drill Monday and President Tsai Ing-wen on Tuesday attended the annual Han Kuang military exercises, although there was no direct connection with tensions over a possible visit by U.S. House Speaker Nancy Pelosi.(Shioro Lee/Taiwan Presidential Office via AP)