What are the features of military operations World War I in 1917

World War 1 began in the confrontation between two military-political blocs – the Entente and the Triple Alliance. On the side of the Entente were France, Russia, England (Japan was also on their side). The Triple Alliance included Germany, Austria-Hungary, Italy, on the side Germany was Turkey. Martial law was declared, the activities of all parties except the communist were prohibited, newspapers, books, processions, meetings, and strikes were prohibited.
The 1917 campaign is associated with the entry into the war of the United States, the revolutionary withdrawal of Russia from the war and the conduct of a number of successive offensive operations on the Western Front (Operation Nivelle, operations in the Messines region, on Ypres, near Verdun, at Cambrai). These operations, despite the use in them of large forces of artillery, tanks and aviation, practically did not change the general situation in the Western European theater of military operations. In the Atlantic at this time, Germany launched an unlimited submarine war, during which both sides suffered heavy losses.