You don’t need one to go there. You need one to GET BACK!
Since last year you need a passport to return from either Mexico or Canada.
You don't. But you'll need it to get back.
June, 2009. A passport card or an "enhanced drivers license" (as issued by a few states and indicating citizenship) will also do. These aren't necessary to enter Mexico, as far as I know, but they are necessary to get back into the US.
Well not just a passport, BUT they have changed the regs on border entry even with Mehico...
http://www.motorlink.cn/html/newsletter/en20100707.html
Beginning June 1, 2009 all persons age 16 and older will be required to present:
* US Passport
* US Passport Card
* State issued Enhanced Driver’s License
* Enhanced Tribal Card
* US Military ID with Military Travel Orders
* US Merchant Marine Document
* Form I-872 American Indian Card
El Paso is FAAAAAR from the safest city!!!
It wasn’t nice to be there in 1963. Much worse now.