Why isn't Mexico part of N.A.T.O?

Question

if NATO is basically an alliance between North America and Europe, and Mexico is our allies, and part of North America, why are they not a member?

Answer 1

Because of WW2, and the fact that Mexico, while it did contribute air forces to the Pac theater, didn't have forces on the ground in Europe at the end of the war.  Also, it was not one of the Western Allied occupying forces in Germany.  Were either of these two situations the case, they would've probably been asked to join.

OK:  the name "North Atlantic" was after the fact.  The occupying forces in Germany became "NATO".  They happened to be on the ground.  It was forces on the ground-at that time-that evolved into NATO

Answer 2

Keywords - North Atlantic. That only encompasses North America and most of Western and Central Europe.

The US has numerous other alliances and treaties to cater for other regions - these include SEATO (now defunct) and ANZUS.

Answer 3

The N.A. in NATO is North Atlantic, not North American. We have other alliances with Mexico protecting them in the same way. Just a different treaty.  

Answer 4

Being a part of North America is irrelevant, as the NATO acronym stands for North Atlantic Treaty Organization.

Using your idea, what part of mexico is in, or borders the North Atlantic, or the Atlantic, for that matter?

They also experienced the Mexican miracle, between 40 and 1980, a period of amazing growth, and Since the Mexican Revolution, and until the administration of President Ernesto Zedillo, Mexico had been known for its foreign policy or "doctrine" known as the Doctrina Estrada, which  was a foreign policy guideline of an enclosed view of sovereignty. It claimed that foreign governments should not judge, positively or negatively, the governments or changes in government of other nations, in that such action would imply a breach to their sovereignty. This policy was said to be based on the principles of Non-Intervention, Pacific Solution to Controversies, and Self-Determination of all nations. Simply, they didn't want to be a member.