I double checked with Carnival to make sure they do not have a corporate policy for passports and they do not. Maybe you were required to have a passport because the cruise was to Honduras. The "Western Hemisphere" is under a diffent policy and those areas include:
Areas that fall under the WHTI:
Canada
Mexico
Bermuda
The Caribbean region (includes 17 regions)
We are going to Jamiaca and the Caymans so we are good to go.
The travel agent did urge us to have them anyways and many of the travelers in our group do but for those who don't this was a great PLUS.
Here is a little exerpt from the travel.state.gov website about the policy:
AIR TRAVEL
ALL PERSONS traveling by air outside of the United States are required to present a passport or other valid travel document to enter or re-enter the United States.
LAND AND SEA TRAVEL
The following summarizes information available on the Department of Homeland Security’s website.
CURRENTLY:
U.S. citizens need to present either (a) a passport, passport card (available in spring 200, or WHTI-compliant document; or ( a government-issued photo ID, such as a driver’s license, along with proof of citizenship, such as a birth certificate.
LATER:
On June 1, 2009, the U.S. government will implement the full requirements of the land and sea phase of WHTI. The proposed rules require most U.S. citizens entering the United States at sea or land ports of entry to have a passport, passport card, or WHTI-compliant document.
Note: The passport requirement does NOT apply to U.S. citizens traveling to or returning directly from a U.S. territory.