Good question. As a Brit, my knee jerk reaction is to blame German militarism but I may get called on this again by A. Saturnus. Even after the retreat from the Marne, the Germans occupied significant territory in the West and would have had to surrender it for a plausible peace. But I suspect they thought they had the upper hand - IIRC 1915 was not a bad year for them - and we all know about the "stab in the back" stuff that happened even when they did finally quit in 1918.Originally Posted by Franconicus
The reverse was probably true in 1916 - the Allies saw a chance for victory and may have wanted to take it. The pendulum swung back and forth for the rest of the war (1917 Germany has an edge; 1918 the Allies). What looks to us like a stalemate probably seemed something different at the time.
More generally, I think there was a wave of patriotism on the home fronts that meant even supposed internationalists like left-wing political parties had to get behind the war or risk being ostracised. Asking for terms in the middle of a war, is likely to lead to politicians losing power at home or otherwise being seen as weak by their enemies.
On the trenches, I think there were still strong traditions of deference and loyalty so that even if soldiers did not hate their enemy (playing football at Christmas etc), they would do their duty for king and country. (Compare with the French Army's collapse in 1940 or even Iraq's in the Gulf Wars).
I'd be interested to hear of any peace-feelers put out during the war. I vaguely recall the Americans pushing for this, but suspect the conditions - centring around national self-determination - would not have been ones that were acceptable to the militarists and imperialists who wanted war in the first place.
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