The US goverment never acknowledged that it was an aggresion war.
Some prominent americans were against the War with Mexico as Lincoln and Toureau.
Still during 1870's, the California congress requested to the US goverment the purchase of Baja California.
on 1967, a small portion of the land ( El Chamizal ) was returned to Mexico due the Rio Bravo / Grande deviated from its course.
In 1917, Germany invited to Mexico to join forces in return of the lost territories with the exception of California, that was planned to be granted for Japan ( Zimmerman Telegram ). The kaiser was merely fooling with Mexico, due it was no way that the germans could supply the men and the weapons promised to invade the US, due the continental blockade against Germany and her allies.
Also, the germans plotted to raise a civil war in the US to proclaim an independent republic of mexican, blacks and chinese. This was the called Plan de San Diego.
On today's political perspective, it is not matter where the borders ends and begins, but the economical and political involment. The wars for conquest are in the past. We have 20 million of mexican born, mexican descendant living in the USA. Around 50,000 mexicans are serving in the US Army. California, considered the 5th economy world wide is sustained on the work of the inmigrant force, mainly mexican. The so called hispanics are nearly to become the first larger minority over the african american.
In terms of cultural introduction, we have been assimilated in the US Culture:
Many americans are affraid of La Reconquista of the Southern, Central and Western states. By the other hand, a bunch of radical " chicanos " are spreading the believe that the lost territories are the ancient Aztlan ( the motherland of the Aztecs ). Both positions are obviously radicalized.
Mexico could not defeat by the force of the arms to the USA, but it can penetrate deep on the roots of the USA and converte it into an anglo-mexican society.
China did the same with every foreigner invader. At the end, they were "chinized". Mexico also has been affected by the US Culture in the process.
Edited by Jalisco Lancer