Why was it not blazed acrossed evey front page paper that Americans were dying/sitting ducks? Ok, Admiral Ernest King gets much blame but what about Roosevelt, the Joint Chiefs of Staff, U.S. Department of Defense. Senators, the press? Silence seems like the very worst approach. "In the first eight months of 1942, German submarines sank nearly 400 Allied freighters and tankers along the U.S. Atlantic coast with a loss of more than 5,000 lives, "
Curious, if in private writings anyone called for greater transperancy, letting the seamen know/have a choice in the matter
While anyone who was a crewmember in the Merchant Marine or an Allied seagoing vessel would be well aware of the threat of U-Boats along the American East Coast (especially since U-Boats had been attacking Atlantic sea traffic well before Operation Drumbeat began), mainly through either crew briefings or word of mouth, news reports of Allied freighters being sunk were suppressed for a two major reasons.
One major reason was to keep the German Kriegsmarine in the dark in regards to just how successful the Operation Drumbeat was. Reports were suppressed by the War Department so that the Kriegsmarine or the Abwehr could not corroborate news reports with reports from U-boat crews as to how successful Operation Drumbeat was going as well as what areas they were, for lack of a better term, getting the biggest bang for their buck. While in hindsight we know that the Abwehr had a very limited footprint in the U.S., they were still able to get ahold of American newspapers through neutral countries as well as listen to American radio broadcasts. Also, while a U-Boat would often be able to report they had sunk a ship, circumstances sometimes dictated that they were unable to loiter on target to confirm a ship's sinking, it's identity, or other key information that would be valuable for later operational planning.
The other is that while the majority of crewmen working Allied Freighters were well aware of just how badly the American Navy was doing in combating the U-Boat threat early on, the War Department saw there was really no reason to broadcast this to the public and risk bringing down public morale. Keep in mind, during the time of Drumbeat, you have several other events occurring that were not necessarily painting an optimistic picture of the U.S. and the Allies winning the war (the loss of the Philippines and several other American outposts in the Pacific, German gains in Eastern Europe, the war in North Africa, etc.). So the War Department sought to prevent news from being widely published that might cause a further downswing in morale.
As far as letting Seamen know the risks they faced and having a choice in the matter, a couple of things here. First as I previously mentioned, the majority of officers and crew working Allied and American freighters were well aware of the threat they faced when they put to sea, either from official sources or from word of mouth. The second is that even though the members of the American Merchant Marine were formally considered volunteers, they took orders from the U.S. Navy, and while nothing was stopping a seaman from leaving the Merchant Marine if they felt the risk necessitated doing so, doing so meant they were eligible to be drafted into the armed services within 30 days. It also meant they would be sacrificing whatever pay and rank they had attained in the Merchant Marine.
Sources:
Bloodstained Sea: The U.S. Coast Guard in the Battle of the Atlantic, 1941-1944 by Michael G Walling
Heroes in Dungarees: The Story of the American Merchant Marine in World War II by John Bunker
Merchant Mariners at War: An Oral History of World War II by George J Billy and Christine M Billy