A lot of mistakes are being made to possibly make this happen.
Check it out:

Former Vice President Dick Cheney on Tuesday predicted the United States would not make it out of the next decade without another terrorist attack, likely much bigger than 9/11.

Cheney, who has made a similar warning a number of times before, said the threat might come from a nuclear device.

“I think there will be another attack. And next time, I think it’s likely to be far deadlier than the last one,” Cheney told radio host Hugh Hewitt. “You can just imagine what would happen if somebody could smuggle a nuclear device, put it in a shipping container, and drive it down the Beltway outside of Washington, D.C.”