As for why we are beefing up radioactivity searches at ports, it should be obvious that a ship can transport a nuclear devise while also enclosing it in said heavy encasing. Satellite detection isnít as reliable when dealing with vessels that can transport huge payloads.
It is also important to note that the US naval fleet needs to defend itself from missile attacks, nuclear or other, as well. Can you justify not defending an entire US carrier group against missile strikes?
If you hack my responses into little out of context pieces, Iíll show you no respect in the future. My paragraphs are small enough to quote so don't be a hack.