MIAMI — When Norwegian Cruise Line announced three years ago that it would hire only Americans to staff one of its ships in Hawai'i, the collective response from cruise industry insiders was "Ha!"

Americans couldn't take the long work days and cramped living quarters, they said. There would be massive walk-offs.

And at first, it seemed like a case of "I told you so."

But Miami-based NCL stuck with the experiment. It sharpened its recruiting strategy and invested in intensive training programs to prepare Americans for the rigors of working on a cruise ship.

NCL recently added a third American-staffed ship, the Pride of Hawaii, to its fleet in the Islands.

"If the proposition is that American workers can't work hard and can't deliver good service, then we have shown that's wrong," said Colin Veitch, CEO and president of NCL. "Has it been easy? Certainly not. There was no labor force experienced in this work. We had to create one."

For as long as modern cruising has been around, ships have preferred to carry foreign flags, allowing them to hire from developing countries that have abundant supplies of inexpensive labor.

The hiring of American workers was NCL's gambit for entering the coveted Hawaiian cruise market. U.S. law prohibits foreign-flagged ships from transporting passengers between U.S. ports without visiting a foreign port somewhere along the way. In Hawai'i the nearest foreign port — Fanning Island — is two days away, meaning foreign-flagged ships typically can't do a Hawaiian itinerary in fewer than 10 days, a turnoff for many people with limited vacation time.