Why did Woodrow Wilson ask for a declaration of war?

Answer 1

The US's closest allies were at war, Germany was sinking ships (like the Lusitania),

In 1917 of March German submarines sank another three American ships . There was also intelligence that showed that Germany was attempting to form an alliance with Mexico against the US.

Answer 2

For all of the rhetoric about Woodrow Wilson being a Man of Peace dedicated to Ending War - - - -the truth is much murkier. World War One began in August 1914, deep into Wilson's first term. At that moment in time Britain & France were running the show - - - So Wilson being an astute Politician found a variety of reasons NOT to go to war - - - Just Yet. The sinking of the Lusitania on May 7 1915 was as good an excuse as any for Declaring War, but No, WIlson had his agenda to tend to and that meant no war until securing a second term.

In November 1916 Woodrow Wilson won reelection on the slogan "He Kept Us Out of War." Sworn in for a Second Term on March 4 1917, WIlson soon asked Congress to Declare War. He had lots of reasons for doing so, the Germans provided plenty of provokation, but the bottom line is that Wilsonalwats intended on going to war and by 1917 an exhausted France & Britain were in a much more concillatory mood.