[Robert357]

What unnerves me is the idea that at this very moment there's a bunch of boats ....

I don't think that boats could be tied up at docks like that. Anchored maybe, but not tied up at the docks. A long time ago, I helped put myself through college by longshoring during the summer as a casual card member of ILWU. Longshoremen may be a lot of things, but they use to be very curious about cargo and about what was aboard ships. Also pilots who bring the ships into the harbor like to know what they are guiding into port. I do think that the article I saw about Coast Guard teams of explosive sniffing dogs and seamen being lowered by wire onto ships prior to entering harbors, is tip off and comfort.

[TrappedInLiberalHell]

I was thinking more along the lines of boats stowed away in the Florida Keys for example, covered with brush to avoid aerial detection, but within hailing distance of a target (they could do the attack on a busy day when LOTS of pleasure craft are in the water). After all, lots of drugs make it into the company undetected, why not a few pounds of Cobalt or some other radioactive material, shielded and tucked in the bilge.

How would we stop such an attack, without advanced knowledge of it, or credible leads that might lead us to scrutinizing such areas enough that the would-be attacker gets caught in the dragnet.

I'm just curious about the feasibility of actually bringing in dirty bomb materials, or C4 for a bridge attack, or a fertilizer-based bomb like that used in the OKC bombing. Or even large quantities of weapons-grade anthrax, stored in a rusty, innocuous looking drum.

The scenarios are endless, it all comes down to plausibility.