Around 1949. When the Axis Capitulated and lost the war, Europe was divided and one half became proxy states, part of the Warsaw Pact. This Large Buildup of Soviet Power caused the US to be Highly suspicious of Communists and communism, which seemed to only Seek power over the West. 
        
             
        
        
        
Be a U.S. citizen.
Be a resident of the Arizona county listed on your registration.
Be at least 18 years old on or before the date of the next general election.
NOT be convicted of a felony (or have had your civil rights restored).
NOT be declared "incompetent" by a court.
        
                    
             
        
        
        
Not only goods but also culture was "traded" along trade routes. The Renaissance was a time period of new thinking. Trade influenced the renaissance because it gave Europeans a contact with other cultures that had perhaps developed newer or better techniques and technologies. For example, the Arabic states had advanced universities and had made great discoveries in mathematics.
        
                    
             
        
        
        
The two reasons:  
- Britain intercepted the Zimmerman Telegram
- Germany resumed unrestricted submarine warfare
Context/detail:
Public outrage in the US against the Germans swept the nation following the sinking of the British ocean liner, <em>Lusitania</em> -- but that happened before 1917.  When a German U-boat (submarine) sank the Lusitania in May, 1915, over 1,000 persons were killed, including more than 100 Americans. The passenger liner was targeted by the Germans because they suspected weapons were being shipped to Britain in the cargo hold of the ship.
Germany managed to stave off American entry into the war at the time by pledging to stop submarine attacks.  But a couple years later they resumed such attacks, and there was also an intercepted telegram (the "Zimmerman Telegram") that showed Germany was trying to secure Mexico as an ally against the United States.  
In 1917, the US declared war on Germany in response.
 
        
             
        
        
        
The Commerce Clause<span> describes an enumerated </span>power<span> listed in the United </span>States Constitution<span> (Article I, Section 8, Clause 3). The clause </span>states<span> that the United </span>States<span> Congress shall have </span>power "To regulate<span> Commerce with foreign Nations, and </span>among<span> the several </span>States<span>, and with the Indian Tribes."</span>