In the first and second paragraph Wilson appeals to emotions by mentioning the American lives lost.
The "War Message to Congress" was delivered by President Wilson on April, 1917, after an armed American steamer was torpedoed and 28 members of its crew died. With that message Wilson pretended to show Americans that, although it was fearful to go into war, the U.S. could not remain peaceful in the face of the agressions suffered by the Germans.