I don't think it's that bad. Firing a flare at it is just acknowledging its presence (unlike the last one which they admitted they failed to detect). If they really wanted to make a point they could have tried shooting it down. Even that wouldn't be that big a deal, it's a drone not a piloted aircraft.
Don’t say we didn’t warn you – Symposium of China’s top think tank sends classic, pre-war warning to provocative Pelosi
"Don't say we didn't warn you!" - a phrase that was used by the People's Daily in 1962 before China was forced to fight the border war with India and ahead of the 1979 China-Vietnam War, was frequently mentioned during a forum held Friday by a high-level Chinese think tank,
"Don't say we didn't warn you" has become a key phrase used by Chinese official media as the most severe warning previously issued before shots were fired in military operations. The phrase has been used several times before, such as in 1962 and 1978, not long before China's military operations against provocations by Indian and Vietnamese troops, respectively.
"The US should not underestimate the Chinese people's determination to defend core interests on sovereignty, integrity and security at any time. It should also not repeat the miscalculation it made in the 1950s in the Korean War. Despite not being strong at that time, China still had the courage to fight a war when it was pushed to the corner, it will surely not sit idly by this time," said Yang.
The countermeasures in China's toolbox include concrete and strategic ones and rapid and long-term ones and it will take different measures in accordance with Pelosi's interactions with secessionists from the island of Taiwan. If she makes the visit, the possibility for China to recall the ambassador from the US cannot be ruled out, analysts said, also referring to imposing sanctions on individuals related to the visit.
… If this can be tolerated, what cannot?" said Leng Bo, an expert from the Institute of Taiwan Studies in Chinese Academy of Social Sciences
If Pelosi insists in making the visit, China can turn the incident into an opportunity to taking control of the Taiwan Straits situation and push the reunification process a step further,
(Wu Yongping, director of the Institute of Taiwan Studies, Tsinghua University,)