What it says on the tin. With a POD after 1900, have the Mexicans with an Aircraft Carrier by 2013...
Note, this does not have to be the size of a current US Aircraft Carrier (nobody else in the world iOTL has one), but if you can justify one the size of Thailand's Chakri Naruebet is fine.
(Getting the United States to name an Aircraft Carrier USS Mexico also qualifies)