e, "the Government of the United States would be constrained
to hold the Imperial Government to a strict accountability for such acts
of their naval authorities."

In the American note of May 13, 1915, the Government stated:

"The imperial Government will not expect the Government of the United
States to omit any word or act necessary to the performance of its
sacred duty of maintaining the rights of the United States and its
citizens and in safeguarding their free exercise and enjoyment."

In the note of July 21, 1915, the United States Government said that--

"Repetition by the commanders of German naval vessels of acts in
contravention of those rights must be regarded by the Government of the
United States, when they affect American citizens, as deliberately
unfriendly."

In a communication of April 18, 1916, the American Government said:

[Sidenote: The United States insists on regard for international law.]

"If it is still the purpose of the Imperial Government to prosecute
relentless and indiscriminate warfare against vessels of commerce by the
use of submarines without regard to what the Government of the United
States must consider the sacred and indisputable rules of international
law and the universally recognized dictates of humanity, the Government
of the United States is at last forced to the conclusion that there is
but one course it can pursue. Unless the Imperial Government should not
immediately declare and effect an abandonment of its present methods of
submarine warfare against passenger and freight carrying vessels the
Government of the United States can have no choice but to sever
diplomatic relations with the German Empire altogether."

[Sidenote: Germany gives definite assurances.]

The German Government replied to this communication on May 4, 1916,
giving definite assurances that new orders had been issued to the German
naval forces "in accordance with the general principles of visit and
search and the destruction of merchant vessels recognized by
international law." And this agreement was substantially complied with
for many months, but finally, on January 31, 1917, notice was given that
after the following day--

[Sidenote: The notice of January 31, 1917.]

"Germany will meet the illegal measures of her enemies by forcibly
preventing in a zone around Great Britain, France, Italy, and in the
Eastern Mediterranean all navigation, that of neutrals included, from
and to England and fro