Yes.
a passport and a plane ticket
Only if leaving country
No - you need a passport too.
You need a passport if you are going to travel outside of the country.
In the northwest states no in the whole world of course every time you travel by airplane internationally you need a passport
Each Individual traveling by Air Travel will need a Passport. Travelers traveling Internationally will also need a passport in order to board an Air Craft.
A passport is when you go abroad and you need that to board the aireopane so they know that you are cheating to get on a plane without a passport
You need a passport to get on a cruise ship to start with boarding pass once you have passed passport control.
If entering Mexico via airplane, yes.
No you need a passport
A passport, a ticket, and a boarding pass.
Yes, you need a passport to cross the U.S. border. If you are traveling by land or by sea, you can use a passport card, which is similar in size to a driver's license. If you are traveling by air, you must use a traditional passport. Considering the fact that a bus will take between 27 to 45 hours to reach Cancun (from the US-Mexico border), I guess your best bet is to take a flight; to board an international flight, you will need your passport.