NCL America's ships are registered in America and they have to have atleast 75% American crew. Nowegian Cruise Line (NCL) ships are registered in Foreign countries and have International staff in the service departments.
The hardest thing for most young Americans taking this type of position seems to be the long work hours.
Just a tip. There are Waiters and junior waiters. The Junior waiters do not get a share of daily tips. The passengers are charged a daily fee for tips when they buy the cruise so unless service is exceptional, The waiter could earn as much as $18 in extra tips. I've seen speciallty resteraunts such as a Japaneese Resteraunt on board where the guests are more generous. There really is no visable difference between a Waiter and a JR Waiter. You work Mornings off for 4hours. Thats your shore time and then you work Diner through close of the Dining rooms. 12hour work days.