They pointed out, however, the futility of treating on the basis of promises alone with a nation which not only had shown a contempt for its ordinary promises, but had repudiated its sacred obligations.
A ray of hope gleamed across our national horizon when Germany, on February 16, sent a note acknowledging her liability in the Lusitania affair.

But the whole matter was soon complicated again by the "armed ship" issue.

Germany had sent a note to the neutral powers that an armed merchant ship would be treated as a warship and would be sunk on sight.
Secretary Lansing made the statement for this government that by international law commercial ships have a right to arm themselves for self-defense.

It was an additional emphasis on the position that the submarine campaign as conducted by Germany was simply piracy and had no standing in international law.

President Wilson, in a letter to Senator Stone February 24, said that American citizens had a right to travel on armed merchant ships, and he refused to advise them against exercising the right.
March 24 the French steamer Sussex, engaged in passenger traffic across the English channel, was torpedoed and sunk without warning.