US already overflies what PRC considers to be her territory, if anything this is PRC retaliating in kind - state media had clip in 2020 of shooting down foreign ballon that landed in mainland but simply didnt make a big fuss over it. It's amusing people think PRC is burning political capital when these overflights will likely continue, there's no reason to stop prodding just because western media throwing conniption about their sovereignty getting violated in retaliation. It's more domestic political nightmare for US than international diplomatic nightmare for PRC.