Can a terrorist atomic bomb strike on a U.S. city be prevented?

Let's say you're an average, hard-working, middle-class American.  You're raising kids, or enjoying being a grandparent or similar.  Statistically, you have almost no interest in foreign policy, military strategy or international relations--and fair enough.  Can't do anything about any of it, so all you can do is hope that the folks you elect to run this place don't screw up too badly.

Or that if they do, the price is paid by some city other than where you and your loved ones live.

Again, fair enough.  We live our lives based on where we find ourselves.

With that said:  For some years now I've been concerned about the possibility of a nuclear attack on the U.S. by a terrorist group.  [links]   Given the global forces at work, it seemed to me that such an attack was virtually a certainty.

As it happens, the "assistant director in charge of the FBI’s Weapons of Mass Destruction Directorate" has the same opinion.  (Caveat: Story is two years old and single-sourced.)  In any event, the question is:  Can such an attack be prevented?  That's the purpose of this post.

Short answer:  Can't absolutely prevent it, but we can reduce the ease with which it can be done.  The harder you make it to do, the less likely it is to happen.

Problem:  The strategy for making it less likely involves taking a position totally antithetical to that of all Democrats, liberals, socialists and leftists of all stripes.  And here it is:

The U.S. would need to quietly make it known--unofficially, through unwritten back-channel contacts--that if a nuclear weapon was detonated in the U.S., and we learned the source of the bomb, we would launch a nuclear strike on a city in the source nation, without warning or negotiation. 

Is this harsh?  Ghastly?  "Group punishment?"  Yes to all.  The point is that we need to convince whatever rational intel and police officials may live in such nations to realize it's very, very much in their personal interest to make a maximum effort to monitor and interdict any efforts to buy or transship nuclear weapons.

In this vein the *tone* of the message's delivery is crucial:  Rather than using diplomatic channels I suspect the best way would be military-to-military--something to the effect of "The U.S. military command structure has determined that *regardless of whether the president orders it*, the military will retaliate..." 

If word of the policy leaked (a certainty), the U.S. government would deny that this was policy--which is exactly what one would expect if it *was* the policy.  And of course the Pentagon would refer all questions to the White House.

Of course, given the craven policies of the Obama administration (whose strategy could be described as "bow and run away"), any foreign military chief or intel official hearing such a message probably wouldn't believe it--a very rational response. 

Can that reaction be changed?  Probably, but to do so will take time and some hard-headed responses to future provocations.  Whether the U.S. government can change its policies of appeasement to hard-headed responses is unknown.  At the moment the entire State Department and a large number of civilian officials in the Defense Department seem determined to support Islamic fanatics (Egypt, Syria) at any cost.

If the Islamist supporters could be fired that would make it immensely easier to change U.S. policy "on the ground."  Unfortunately, like the Soviet spies in the CIA back in Angleton's day, Islamist supporters seem to be protected against purges by like-minded colleagues at the highest levels of both agencies.

Throw them all out.