Yes, you need a passport. If you are leaving the USA and going to Mexico then you need a passport.
if you are going on a cruise that goes out of the country, you will have to present a passport anyway.
Yes, you do. Especially if you are entering Mexico by air-flight.
No. As reaching the island of Cozumel will require you to board a plane, most probably you will require a passport, either to board the plane or on your way back.
From the USA, yes, you need a passport.
Yes, you need a passport. When you travel to other countries by plane,car,ship you should always have you passport along.
just to be safe you should probably take it, but keep it safe and don't misplace it!
Check with Carnival's website. If I remember correctly, you can use either a passport or your driver's license and a birth certificate. I've taken three cruises with Carnival and I've always used a passport.
Basically yes, to get on AND off the cruise ship you need a passport.
yes you do need a passport throghout the cruise, especially to get out of the Bahamas visitor center,but when you go back on the cruise they will give you a carnival card.
yes
US citizens cruising to and from a US port do not need a passport.
Yup
I have visited the Bahamas and yes you need a passport its a different country proved by they drive on the other side of the road.
do children need passports to take a cruise?
On most cruises yes. But not on "Closed Loop cruises" see http://getyouhome.gov for all the passport rules!
If you are a US citizen, and the cruise ship departs and returns to the same US port, you will not need a passport to go on the cruise - as long as the cruise ship does not stop in any countries that require a passport for US citizens. If the ship is only cruising in Mexico, and returns to the same port from which it departed, you can board the ship with a certified copy of your birth certificate and a government issued photo id. It is much better, however, to have a passport. If, for example, there is an emergency and you have to leave the ship and fly home from Mexico, you will need a passport.