Question

the cartoon on the left was published on february 1, 1917. the letter from germany to uncle sam reads:
uthless warfare at sea. ships enter blockade zone at their risk. pledges as to warnings cancelled.\ what was the effect of the message shown in this cartoon? the united states declared war after the u.s.s. maine was blown up in havana harbor germany announced it would not attack passenger ships or merchant ships without warning the united states declared war after germany sank american ships in the blockaded zone the zimmerman telegram offered texas and california to mexico in exchange for an alliance

Explanation:

The cartoon shows Germany's unrestricted submarine warfare (ruthless warfare at sea, cancelling warnings). This led to the sinking of American ships. The U.S. declared war on Germany in 1917 after such incidents. The USS Maine incident was in 1898 (Spanish - American War context, not related here). Germany's announcement in the cartoon is the opposite of not attacking without warning. The Zimmerman telegram is a different event (though also a factor in U.S. entry into WWI but not directly related to this cartoon's message about unrestricted submarine warfare).

Answer:

The United States declared war after Germany sank American ships in the blockaded zone.