Lessons - yep there are lessons.
When you go to war - you step in to a dark room. You hopefully have prepared yourself with the best equipment, training, operational concepts possible. The wise commander steps in to that dark room knowing that he will not know what will happen when he enters. At first, he won't see what works and does not - but he looks for it.
He adjusts, he modifies - he tries to find advantage.
Remember the FbF the other day about the Australian Light Horse and the assault on Beersheba? The Germans then did not think that mounted infantry would fight as cavalry - though the Commonwealth leadership saw the need to improvise, adapt, and overcome. Victory came to the less myopic leader.
Now the other side of the coin. You have cavalry. Always go back to one question: what is the mission.
General de Witte, Belgian Army knew what to do.
On the morning of August 12, the German cavalry arrived at Haelen and prepared to cross the bridge there.Fight with what you have. Fight for every hour - as those behind you need every one.
Units of the Belgian cavalry (the 4th and 5th Lansiers, plus a company of cyclists and another of pioneer engineers) under General de Witte ambushed the advanced squadrons of the German cavalry, in what was almost certainly the last fight between mounted cavalrymen, wearing the breastplates and helmets of a different era.
(at the bridge, the Germans) encountered a prepared Belgian cavalry, fighting under General de Witte. The two cavalry fought throughout the day. The significant difference between the two cavalry was that the Belgian cavalry dismounted and fought as infantrymen.
The Germans launched numerous and repeated attacks against the Belgian forces but their sabers and lances could not hold against the unexpected Belgian rifle fire. The Germans fought until 6pm that evening having begun the attack around 8am. Frustrated Marwitz and the German cavalry were forced to withdraw from the bridge at Haelen that evening.
In all the Germans suffered nearly 1000 casualties that August day in 1914; 200 – 300 were taken prisoner by the Belgians, 150 were killed and 600 Germans were wounded. Belgian forces suffered approximately half that number in casualties.
Von Marwitz withdrew, advancing days later with great caution. This battle grew in Belgian folklore as the 'Battle of the Silver Helmets'.
The Battle of Haelen was a tremendous victory for the Allied Forces. Although the Belgians held the bridge at Haelen, the remainder of the German army won the Battle of Liege on August 16 and the German army continued their advance through and takeover of neutral Belgium.
For the USA's population of ~307 million today - that equates to 573,066 dead.