Was he that dependent on aid from the Western Allies? Did he think the Germans were like a wolf held by the ears? Why did he try to launch an offensive, when the army could at best be trusted to resist an invasion? In hindsight, one of history’s great blunders. But why?
From what I remember, the Allies put the pressure on Kerensky to remain in the war. In addition, you can’t just quit a war: the Germans would insist on major concessions. Kerensky was not willing to give up the territory that Germans would want.
Lenin OTOH, didn’t worry about losing territory and ceded Estonia, Latvia, Lithuania, Belarus, and the Ukraine to Germany. That’s a big price to pay.
Lenin probably realized that Germany would lose to the Allies, especially since the US entered the war. This happened after Kerensky took power, and the US didn’t start sending troops until after Lenin took over. Without the US entry, it was a strong possibility that Germany might not be defeated and end up keeping the territory after the peace treaty. Germany’s defeat allowed Lenin to take back the areas he ceded.
I broke out “A People’s Tragedy” by Orlando Figes, a brilliant book about Revolutionary-era Russia. Figes concludes the reason Kerensky stuck to the war was that he thought it was the only chance to keep Russia from sliding into the hard left camp. It was clear by the summer of 1917 that the masses backed the two main anti-capitalist and anti-private property parties, the Bolsheviks and the peasant based Social Revolutionaries. Kerensky felt that if he could achieve military victory a grateful nation would swing back to more moderate policies.
Why did he keep believing this even as the evidence mounted against victory? Kerensky was a stubborn, incredibly vain man who viewed himself as Russia’s Napoleon. He adopted military outfits and even wore a arm bandage for a while, even though he never spent a day in the military. His generals and fellow cabinet members warned him the nation was tired of war but he didn’t want to listen.
The German terms were so harsh that even Lenin initially balked at them. The Germans had to launch a new offensive to convince him to sign the treaty.
As for overturning the treaty, Lenin was counting on the spread of revolution more than hopes of an Allied victory. Lenin figured that within a few months, communists in other countries (especially Germany) would follow the Russian example and overthrow their governments (which was not an unrealistic hope in 1918). Then Lenin would be able to negotiate a more equitable treaty with a fellow communist regime.
As it was, Germany bungled the diplomacy by losing sight of the big picture. Yes, they had Russia on the ropes but their big problem was on the western front. They needed to finish off the war in the east so they could move troops over to the west for a final offensive before the Americans arrived. Germany should have offered Russia easy terms and got a quick settlement. Instead they wasted badly needed time by insisting on harsh terms.