No Sail List?

[megmno]

Ok, I have this weird hypothetical question:

 

When you go through security to get on an airplane, they check your name against the Homeland Security "no fly" list. Occasionally, people get stopped from boarding due to a match being made with a name on the list. Usually, after questioning, it turns out that it was a false positive due to a similar name or something like that. Occasionally, the person has to be put onto a later flight if the original flight takes off without them.

 

So, we know that passenger manifests for cruise ships are transmitted to Homeland Security before sailing. What happens if a passenger is flagged as a potential threat? I presume that he is stopped before he boards the ship. Would the port authorities hold up the sailing of the vessel until a determination is made about the passenger, or would the ship sail without him? If so, and it's just a false positive (i.e. he's not a threat) how would he be compensated, and by whom?

 

Just my idle curiosity late at night....