The Kerensky Offensive was supposed to prove that the Russian Provisional Government was in control and that Russia could still field an effective army. Instead, it demonstrated that neither of these were true.
The Kerensky Offensive provoked discontent among soldiers in Petrograd which triggered a Bolshevik uprising against the Provisional Government. The uprising was put down and evidence was made public that the Bolsheviks were being supported and funded by Germany.
With the Bolsheviks relentlessly criticizing the Russian government, the question of war aims came to the fore. When the liberals in the government couldn't give a straight answer, a cabinet shuffle followed, giving socialists more power than before.
The Russian Provisional Government had declared a political amnesty that allowed political exiles to return home, notably Leon Trotsky and Vladimir Lenin, who got an assist from the German government.
The US entered the war in early 1917, but it would take time for her to have an impact on the war. Brazil also joined the war in 1917, and in Canada, the political fight over conscription leads to a divisive general election.
By 1917, many in German and Austrian official and military circles had given up hope of winning the Great War on the battlefield and were ready to discuss peace terms. Hindenburg and Ludendorff, however, insisted that victory was at hand.