war. The 8 million tons of bombs that the United States dropped during the Vietnam War likewise accomplished little and may even have been broadly counterproductive, serving to secure the civilian populace’s support for communist war aims while alienating the American public.
It may be impossible at any level of bombing short of nuclear use to collapse a regime from the air. The closest that any operation has ever come was the NATO campaign against Serbia under Slobodan Milosevic, but even there the bombs stopped dropping in June 1999, while Milosevic’s regime fell to mass demonstrations in October 2000.
The chances of the Iranian regime collapsing entirely through the application of airpower were slim to none, so the next impossible thing demanded of the U.S. military was to neutralize Iran’s ballistic missile and drone capacity, also entirely from the air. But this mission—disabling mobile launch capability with minimal ground forces—has also been tried repeatedly before and has also never succeeded.
In WWII, both American and British air forces made substantial efforts to shut down V-1 flying bomb and V-2 rocket production and launches through an extensive bombing campaign, codenamed Operation Crossbow, but they could not stop the launches. It was simply too easy to harden or conceal production and launch sites.