Did the weapons in World War 1 work

Oh, my goodness, yes, the weapons of WW1 worked - far too well. A figure of approximately 40,000,000 casualties should give you an idea of just how well. The biggest problem was that, very like the American Civil War, the tactics had not kept pace with the advances in technology, and the commanders were often not flexible enough to recognize this salient fact.

WW1 saw the first use of the airplane as a weapon; the tank was invented in WW1; the machine gun was horribly effective, especially in the early days of the war against massed infantry assaults which now seem almost quaint in their 19th Century simple mindedness. The artillery of WW1 was vastly more deadly than anything that had ever been seen before, and there had been an arms race ever since 1871 that saw all sides developing new and more horrible ways to kill one another at longer and longer ranges. The Germans first used flame throwers at Verdun. Barbed wire may be considered a weapon in that it hung up those massed infantry assaults and allowed the men to be slaughtered by rifles, machine guns, mines, flame throwers and grenades. The Germans also introduced poison gas for the first time in warfare, which was used by both sides and, while not decisively effective, remains one of the most remembered horrors of the First War. The simple bolt-action rifle with bayonet was the least of the soldiers' problems.