The problem for any serious shoot-down attempt is how this played out.
- Pelosi's trip is leaked to the press
- China did not like that
"Public opinion cannot be defied. Those who play with fire will perish by it. It is hoped that the US will be clear-eyed about this," the statement [by Xi Jinping] said.
- Biden appeared to demur on it
Biden said that “the military thinks it’s not a good idea right now,” but he noted that he was not sure “what the status of it is.”
- A Chinese official suggested the plane could be shot down (Twitter removed the post in question)
“If U.S. fighter jets escort Pelosi’s plane into Taiwan, it is invasion. The PLA has the right to forcibly dispel Pelosi’s plane and the U.S. fighter jets, including firing warning shots and making tactical movement of obstruction. If ineffective, then shoot them down,” Hu Xijin, an analyst for the Chinese state-controlled Global Times, said on Twitter Friday in a post that has since been removed by the platform.
- Pelosi goes to Taiwan anyway
Would the Chinese shoot down a US head of state? Probably not. In fact, if anything, their statement made it less likely she would get shot down. In brinkmanship, you want to do things that irritate your counterparts without provoking a response. Xi's comments were just vague enough to be understood, but not viewed as a direct threat. Threats as blunt as the one issued later are pretty rare because China does not want a military confrontation with the US. The US has a significant military presence in the area, so it would be hours, not days or weeks, before any response could be taken.
Moreover, let's say someone else (North Korea, Russia, etc) decided to try and sent an asset to shoot her plane down. China would immediately be blamed, regardless of whomever did the deed. The Chinese, thus, had a powerful incentive to make sure nobody else interfered with her trip.
A shoot-down would also dramatically shift public opinion for both the US and China. China uses Taiwan to help build nationalistic pride
China’s official position, which it has repeated almost by rote for decades and drilled into its citizens, is that Taiwan has always been part of China and therefore its separation from the mainland is intolerable. This has given the pursuit of political control of the island an unquestionable, almost divinely ordained quality. For a nation whose governing ideology of communism is strongly at odds with its economic realities, nationalism has increasingly become the go-to binding force in public life—and with cynicism about the country’s system running high, especially among educated urbanites, pursuit of the absorption of Taiwan still spurs a unified sense of purpose, acting as a kind of nationalist catnip.
While the downsides of war are obvious, the current political climate allows Beijing to use Taiwan as a way to distract from domestic problems (in much the same way Russia's war with Ukraine does). Actually capturing Taiwan would be far from an easy thing (as Ukraine has recently proved), and would leave leaders without an easy target to keep national problems focused on. People would naturally drift to other subjects, which could lead to discontent. Better to let Pelosi have her trip and then beat the drum of your state-run media, than to shoot her down and harm your economy (sanctions would be the minimal response they could expect), and drive discontent with the government.
Remember also that Pelosi is a Democrat, and Democrats tends to favor less overseas wars. Killing her would divide the Democrats, and leave room for a new, potentially more hawkish, leader. Republicans would almost certainly be united in supporting any actions taken. Remember, in the wake of Pearl Harbor, support for the US entering World War II hit 97%. This wouldn't be as galvanizing, but it would galvanize the US sentiment, nonetheless.
There would be no obvious benefit to shooting down Speaker Pelosi's plane, while the downsides would be very dire, including possible open war with the US.