Here is the correct order of events leading to the United States shifting from neutrality to engagement in World War I:
- Archduke Franz Ferdinand of Austria-Hungary is assassinated. (June 28, 1914)
- Germany attacks and sinks the British ship RMS Lusitania. (May 7, 1915)
- President Wilson institutes a preparedness plan for the United States. (1916)
- British intelligence intercepts the Zimmerman telegram. (January 16, 1917)
This sequence represents the timeline of significant events leading up to the U.S. entry into the war.