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human
{Reign of fire} World's military vs dragons

Just watched Reign of fire 2002, i enjoyed it, especially van zan. 

A question that struck me was, how the world's armed forces seem to overrun quite quickly. 

Surely america/russia/china, and any other world power with a significant air-force, would  see the imminent threat coming from London, would scramble the F16 etc and blow the dragons out of the air. Not to mention the anti air guns major military's have.

So what exactly happened that trillions of dollars of hardware didn't make a bigger dent?
gpt
The old militaries were built specifically to fight other militaries. Despite the fact that toward the end the most powerful and technologically advanced militaries were fighting third-world insurgencies, the purpose of their armies, navies, and air forces was to fight other armies, navies, and air forces. That's how they were organized, that's what they had in mind as they designed tactics and technology. 

When the dragons first showed up, it was unlike anything our militaries were trained or built for. They're more maneuverable than attack helicopters, they can be nearly as fast as fighters, they showed up almost immediately in incredible numbers, and the result was we weren't able to keep up. A few Apache helicopters could take on one dragon, but we were outnumbered 30 to 1 by the time we realized the reports were actually true. Not only that, but the dragons were built for hitting basic infrastructure, interrupting supply lines faster than we could defend them. The Great Planes of the United States were burning within a week of the first sighting. Trucks moving supplies were easy targets. No military can be everywhere at once. We hit what looked like smaller nests with bombs, tried to strike them with missiles, but for every 1 we killed, a dozen took its place because of their incredible reproductive and maturation cycle. Eventually, there was almost nothing left but isolated pockets of resistance and submarines, but even they ran out of supplies. 

The idea that there was a home-base for them wasn't even fielded until after most militaries were in ashes. It was luck that a small group of spec-ops were able to get across the Atlantic from the US to strike London, and even all but one of them died taking on the Father dragon.