- Berlin, January 19, 1917 On the first of February we intend to begin submarine warfare unrestricted. In spite of this, it is our intention to endeavor to keep neutral the United States of America. If this attempt is not successful, we propose an alliance on the following basis with Mexico: That we shall make war together and together make peace. We shall give general financial support, and it is ...lib.byu.edu/~rdh/wwi/1917/zimmerman.html