[Joker_vD]

> Haig wanted to use tanks to brake through German lines, the hole should then be exploited by horse mounted cavalry.

That makes a lot of sense actually. For example, Red Army has shrunk its cavalry dramatically during the pre- and early WW2 period, down to 13 divisions (about 80 thousand people) in favour of tank divisions... and then when the Germans came, the Soviets suddenly found themselves lacking highly mobile forces, so they reverted that decision: during the 1941, almost 110 new cavalry divisions were created. And the Soviets have been using cavalry (in form of cavalry-mechanized groups: tanks plus cavalry) throughout the rest of the WW2 precisely for the purpose of penetrating deep into the rear of the German lines and interrupting supply and reinforcement movements there. And no, they weren't charging with swords drawn, they were essentially mounted riflemen.

So Haig was pretty much on the spot: make an opening with tanks, rush into it with cavalry. Sure, mechanized corps would perhaps be better but you gotta fight with what you have.

[mcguire]

Yes and no. The problem is that in WWI, the fronts were miles deep. There were several connected trench lines backed by guarded supply, artillery, and HQ positions along with the reserves. Those breakthroughs that did happen (which never actually included cavalry, IIRC) tended to bog down, giving the enemy time to bring up reserves and counterattack.

Cavalry and machine guns don't really mix.

[hef19898]

True. Everything I saw so far doesn't show that Haig came to that conclusion put of an understanding of armored or combined arms warfare but rather from sticking to tactics he knew. And IMHO the reason why you come to a conclusion can be as important as the conclusion itself.