How did the zimmerman telegram lead to extent has america lived up to its founding values?

The Zimmerman Telegram was captured, translated from the English in Room 40.  Mexico was told to join the central powers side and in return they will get west, and southwest back from the USA.  

Once America gets land, they will not get it back, part of the idea of Manifest Destiny.  America can not afford to lose California, and other states.   

The second , larger puritan colony of massachusetts bay was conceived as a "city upon a hill". but it also struggled with internal turmoil like the salem witch trials and external conflicts like king philip's (metacom's) war.