My Great Uncle (My grandfathers brother) was a marine who fought in the Pacific Theatre (Saipan, Tinian and Iwa Jima). Before he passed away, he talked a great deal about his time during WWII. He had quite a few friends who ended up fighting (most dying) during this famous invasion on the beaches of Normandy. I asked him this question as well and he was equally upset that there wasn't much in the way of defensive tools provided to those soldiers who stormed the beaches.
Watching the beginning of Saving Private Ryan a few minutes ago reminded me of this thought I had a while ago: We had access to, even back then, material that was impenetrable to 50 caliber rounds. Would it have been absurd to have each dropship equipped with a plate of this material, with handles attached so the soldiers in the very front could hold onto it and move the group up the beach?
I understand fully that a lot of soldiers never made it close enough to the actual beach and were forced to jump overboard into water that was far deeper than a standing adult, but there were still a very large number of dropships that made it close enough to disembark onto "dry" land, but the moment those dropship doors went down, so many soldiers were just mowed down by machine gun fire.
It just seemed absurd to me that the masterminds behind this attack didn't think of any type of defense for this type of charge, even though they knew the casualties would be so immense.
I apologize if this comes off as naive or crazy, but it's been something that's bothered me for a while and watching this movie again brought back this thought.
Ok, let's first note that 6000 deaths is not actually "immense" for a battle of this size.
Second, your question applies with even greater force to attacks across no-man's-land in the Great War. Why weren't the soldiers provided with armour plate to stop them being gunned down by the hundreds? The answer is threefold.
Men cannot carry, by unaided muscle power, metal armour thick enough to be useful against heavy-calibre machine-gun bullets. This actually remains true even today; the body armour worn by modern soldiers protects against shrapnel and glancing hits, but it won't do anything against a direct hit by a .50-calibre machine gun round.
In spite of the evil reputation of the machine gun, artillery was still the main killer of the war.
They were eventually provided with such armour. It's called a 'tank', and gets around the "unaided muscle power" thing by using a combustion engine.
"material that was impenetrable to 50 caliber rounds..."
Can you comment further on this material? Concrete will stop a 50 caliber round, but for obvious reasons that couldn't be put on a landing craft because it would cause it to sink. One of the reasons the Higgins boat was so popular among generals involved in the planning stages of D-Day was that it was entirely constructed of wood. This allowed the boat to have a shallow draft, which would cause the landing craft to float over the defensive measures that were in place in the surf (hemmbalken, Belgian gates, etc.) The Normandy landings took place during a rising tide, so landings had to be specifically coordinated so as to avoid sandbars (which they didn't) and the aforementioned beach obstacles. The lightweight, shallow draft Higgins boat did the job, while offering a decent amount of protection from direct machine gun and small arms fire.
It should be noted, as planned, there was to be armor supporting the infantry in the early waves, however much of it never made it to the beachhead, having foundered en route (the duplex drive tanks).
Also, there was an expectation that the German positions would have been softened up by air support, however due to cloud cover, most of the bombs intended for the defensive lines were dropped further inland in the misguided attempt to avoid blue-on-blue fire, and thus landed harmlessly in fields/open ground.