WI General John Monash died before the Battle of Hamel?

General Sir John Monash of the Australian Imperial Force was one of the key pioneers of armoured and combined arms warfare. He was the one who led the Australians and Americans to victory in the Battle of Hamel, which served as an important tactics testing ground for the later Battle of Amiens (where he was also one of the commanders). Later, he would be described by Field Marshal Bernard Montgomery as "the best general on the western front in Europe" in WWI.

However, let's say that John Monash was shot or otherwise eliminated before his victory at Hamel. His combined arms and armoured warfare tactics go untested in the field, and thus the British (not to mention the rest of the Entente) contine on with their normal strategies, at least for the time being.

Would WWI have dragged on longer in this case? Could it have even led to the war being won by the Central Powers, or a peace deal based on status quo ante bellum? How long would it be before amother person with Monash's mindset and authority came along to give a practical demonstration of combined arms tactics?

And just for a snapshot of what was actually going on in that mind of his, here's one of his quotes, where he describes his frustration with British tactical thinking and how he thinks things should be done:

"The true role of infantry is not to expend itself upon heroic physical effort, not to wither away under merciless machine-gun fire, not to impale itself on hostille bayonets, but on the contrary, to advance under the maximum possible protection of the maximum possible array of mechanical resources, in the form of guns, machine-guns, tanks, mortars and aeroplanes; to advance with as little impediment as possible; to be relieved as far as possible of the obligation to fight their way forward."
 
The War probably wouldn't drag on much longer than it did in OTL. Keep in Mind, Sir Arthur Currie and the Canadian Corps developed new strategies and ways of conducting themselves that led to the victory at Vimy Ridge in 1917. Those strategies ended up being so effective, that even the Germans started using them, including the famous "creeping barrage".

However, the loss of Gen. Monash would've been a very grave loss tot he Entente; he was a very capable commander and very useful and important to the Entente victory.
 
The key event of late 1918 was when Currie force-marched the Canadians into position beside the Australians and both went on the offensive. These 9 divisons engaged 82 German divisions and advanced continuously until the AIF mutinied. Without Monash I think this still may have happened as the AIF corps was performing well under Birdwood.
 
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