As General Ritchie said, NATO responded quickly and effectively, not only by mobilizing fighter jets, but also by convening a meeting of the North Atlantic Council the next day under article 4 of the North Atlantic Treaty. That means Poland felt threatened and wanted to tell its allies that it needed help, while signalling to its adversaries that they had gone a bit too far. NATO responded quickly by establishing a military activity called Eastern Sentry, which gives the Supreme Allied Commander Europe, or SACEUR, permission to move forces from elsewhere to the eastern front to protect NATO airspace. So it's a coordinated, rapid and determined response.
