Reply #42: "I think they'd have a hell of a time smuggling it into the United States"

[Statistical]

Thousands of metric tons of drugs enter the country ever year.
So do million of illegal immigrants.

Almost a billion shipping containers enter the US ports. Nobody is checking them 10km offshore. Only a tiny fraction are even checked and those that are checked are done so when offloaded.

Lots of cargo ships leave from unfriendly ports (Yemen, Qatar, whole host of African nations) where corruption is rapmant and security lax.

Cargo container + nuclear device + some lead shielding + suicide operator + (optional) couple tons of Colbalt-60 or Strontium-90

Ports enters harbor and docks and port. If it is detected operator detonates device as ground burst. If not it can be moved to an optional location.

The only thing preventing a nuclear attack on US soil is their inability to acquire a nuclear weapon. Homeland Security is a joke in terms of preventing a nuclear attack.