Question

why did the zimmermann telegram between germany and mexico concern the united states?
○ germany promised to supply mexico with u - boats to attack american commercial ships.
○ germany promised to set up a king in mexico undermining democracy in the americas.
○ germany promised to help mexico reconquer texas, new mexico, and arizona.
○ germany promised to invade the united states across the texas - mexico border.

Explanation:

The Zimmermann Telegram was a secret diplomatic communication from Germany to Mexico. In it, Germany proposed an alliance with Mexico, promising to help Mexico recover the territories of Texas, New Mexico, and Arizona if Mexico joined the Central Powers in World War I. This threat to U.S. territorial integrity (regarding the return of those states to Mexico) and the potential for Mexico to become a hostile force on its southern border concerned the United States. The other options are incorrect: Germany did not promise U - boats for attacking American commercial ships in this context (the U - boat warfare was more about unrestricted submarine warfare against Allied ships generally), nor did it promise to set up a king in Mexico or invade the U.S. across the Texas - Mexico border as part of the Zimmermann Telegram's proposal.

Answer:

Germany promised to help Mexico reconquer Texas, New Mexico, and Arizona.