If you start with the proposition that the enemy (for sake of discussion enemy = Muslim extremists) yearns to kill infidels whenever possible, then the announcement that they may attempt to use IEDs (Improvised Explosive Devices) on our home turf is disturbing but hardly surprising.

The Times Square attempted bombing was, in a broad sense, an IED. Richard Reid's shoe bomb? Same thing. The underoos worn by the Christmas Day moron? IED. The endless news stories of IEDs in Iraq and Afghanistan have conditioned many back home to think that "IED" stands for "a bomb planted in the road targeting military convoys."

In reality, any explosive device disguised or hidden with the intent of killing infidels qualifies. --When it comes to getting all blown up it doesn't pay to get all technical with definitions.

So when the Department of Homeland Security (DHS) releases a memo stating that terrorists may try to kill innocent women, children and men in the United States by hiding IEDs in luggage left at airports, we should certainly react with vigilance but not surprise. Never surprise.

This is what pathetic, cowardly, psychotic individuals classified as terrorists do...they look for ways to indiscriminately kill and terrorize their enemy. Hence the name "terrorist". What... we're startled that they would include something like this in their playbook of potential operations? Al Qaeda and their band of like minded minions will consider whatever they think might work.

How to defend against this potential threat? First and foremost the public has to avoid terror fatigue. Nine years on from 9/11 and we've all become complacent at times. But the best defense we've got in places such as airports, train stations and other hubs of activity is the awareness and alertness of the public to unusual, odd or disconcerting activity or behavior.

It's become a bit trite, but it's still vitally important..."If you see something, say something." If we depend solely on the various agencies charged with homeland defense to keep us safe, we remove the best and most plentiful resource we have -- the public.

The next critical component is an integrated community of local, state and federal agencies working in concert...sharing information, acting jointly on operations and learning constantly from each other's best practices. Does this happen all the time? No... But it does work a great deal of the time, and all those involved are constantly looking to improve.

We'll never get a perfect system of information sharing and cooperation, just like we'll never reduce the risk from another terror attack down to zero. Won't happen. But as with many unobtainable goals in life, it doesn't mean we shouldn't try.

It's not coincidence that we haven't been successfully attacked on our turf since 9/11. It's not because the enemy has lost their desire or motivation. The reason is a combination of hard work here by Americans here at home to identify, disrupt and prevent attacks and the ongoing effort to dismantle Al Qaeda and its supporters overseas.

Working at home and abroad, we've reduced (not eliminated) their ability to train capable recruits, plan operations and bring the fight to our house.

The DHS memo reminds us, as if we needed reminding, that we must remain aware and vigilant. The enemy will continue their efforts and the odds are we won't stop every attempt. That's not an indictment of DHS or any agency involved in the fight, it's simply a pragmatic look at the odds of trying to be right all the time.

And if something does happen, the proper response is anger and resolve, not surprise.

Surprise should not be in our playbook. Surprise should not drive how we respond to a successful attack. Never be surprised at the ruthlessness and determination of the enemy we continue to face.

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