[david5616]

What are the security procedures for detecting nukes, and how easy are they to possibly conceal or shield?

[constitution]

Sorry, but I've been off on an Afgani site [nothing to report]. Any radioactive material can be detected by a scintillator at some distance. To shield it requires a lot of lead, or similar material. Also there has to be some 'trigger' to compress the radioactive material into a 'critical mass'. Not likely to be easy to hide.