The potential for another attack on the US is probably no higher today than it was prior to 9/11.    All through the 60s, 70s and into the 80s  Billions were spent in the name of defending the country from Soviet missiles. The rise by some of the craziest world leaders, Saddam Hussein, Assad, and the family of wackos in North Korea, all have been concerns to our security.  Not to leave out the Chinese we have feared for decades.  

The concerns about the Mid East and ISIS  being the greatest threat we need to fear above all the rest of the world might be just a bit over played, as we focus on terrorism from Muslims over potential from the rest of our enemies.  Not that the ISIS followers are not a threat, its the rest of the crazies are being presented at a lower level of concern.

I fear we spent all the attention on ISIS and not enough on the reaming list of enemies. Are we getting to friendly with Russia and forgetting the long history of aggression we use to be so concerned about.