The telegram was considered perhaps Britain's greatest intelligence coup of World War I and, coupled with American outrage over Germany's resumption of unrestricted submarine warfare, was the tipping point persuading the U.S. to join the war
So they could be free to practice their religion without persecution.
Answer: The growing political tension between the US and Germany
Explanation: Germany started to take drastic measures and one was that a german submarine attacked merchan ships that had civiles on board