I'm curious, friend, what do you think the air force does when they aren't flying planes in war zones? You think the whole air force lounges around on the ground relaxing, waiting to see if anything comes up? Of course not. They train constantly so that they're ready to be deployed or ready to respond to whatever threats arise. Shockingly, all kinds of military, law enforcement, and emergency personnel spend more time training than they actually spend using that training, since most of the envisioned scenarios never arise for the people who train for them.
The air force exercise you're referring to was conducted semiannually and envisioned a Russian bomber attack; the Russians were conducting their own similar strategic exercises at exactly the same time. On any given day in this country I'm guessing there are at least hundreds of exercises going on at various levels, from the air force simulating Russian attacks to your local county SWAT team taking down a simulated hostage taker. Thousands of governments, millions of people, billions of taxpayer dollars waiting to be spent--they train, train, train, constantly, everywhere, trying to be prepared to stop exactly what we're complaining about.