The u. s. declared itself to be neutral during the war, but allowed u. s. businesses to loan money and sell arms to one side and not the other. in your opinion, 1) was this true neutrality, and 2) did this justify german attacks on u. s. shipping?

No I do not believe that this was true neutrality because you are supporting one side of the war. So in a sense I feel like yes, the Germans were justified in sinking American shipping because this was an act of war on America's part. All's fair in love and war.