PS: Thanks to the book friend "Open? Tips", continue to ask for recommendation votes ^_^

However, the reason why the Americans made such a choice was not entirely out of the psychology of "persimmon picking and pinching," and it was also a very important reason to fundamentally eliminate the threat of the Axis powers, especially German submarines, on the Atlantic route.

The invention of the snorkel made the advantages of the German drop-shaped submarine fully exerted, even though the US and British Navy had a full 50 escort aircraft carriers in service, in the second half of 1942, the loss of the merchant fleet and even combat ships still did not decrease much, almost every month the allies have more than 1 million tons of merchant ships sunk by the submarines of the Axis countries, and the loss of escort ships is also amazing, in half a year, the allies alone escort aircraft carriers were sunk 11 (not counting the two killed by the main fleet of devils) as much, This number is even greater than the total losses of Allied escort carriers during the entire period of World War II in history. There is no way, the concealment of the snorkel teardrop submarines is really good, and the hydrogen peroxide torpedoes can attack from 10 kilometers away, and the track is almost invisible and unguardable, so that they dare to attack any powerful allied fleet, and quietly retreat after firing the torpedo, the US anti-submarine ships often have to be attacked before they can react, and it is too late to chase after then, In this era, there was no towed sonar, so that the anti-submarine aircraft were completely helpless in the face of German submarines equipped with radar wave detection devices on the snorkels and could give early warning

Still, the U.S. Navy staff, who had the best analytical skills in the world, identified the only weakness that German submarines could exploit, and that was that they always had to liaise with headquarters or other submarines. At this point they must float. In this case, if it is close, it will immediately send planes to kill it before it has time to dive or when the depth of the dive is not enough, and if it is far away, then a large number of anti-submarine ships will be concentrated to carry out a dragnet search for that general area, although this may not necessarily be able to find out, but at least the success rate is much higher than that of the previous method.

The approach quickly paid off, and the Germans lost nine snorkel teardrop-shaped submarines in less than a month, a figure that exceeded their previous losses combined. Thankfully, none of the nine submarines surrendered to the enemy. Therefore, the Americans have not yet received the physical object of the snorkel teardrop-shaped submarine. Otherwise, it would be bad if they found out more weaknesses.

Since Hu Weidong had mentioned that submarine communications could be dangerous, especially for relatively expensive teardrop-shaped submarines, Dönitz responded quickly. He immediately ordered that all future drop-shaped submarines no longer need to communicate with headquarters once they leave the port. In addition to the area of operation and the type of mission specified before departure. The rest was decided by the captain himself, and the method of multi-boat joint operations was basically no longer used, and the snorkel teardrop-shaped submarines were mainly single-boat "safari" combat methods since then

So. The Allied anti-submarine warfare became even more difficult, and the only relief to Roosevelt and Churchill was that this method of warfare also greatly reduced the combat effectiveness of the enemy's submarines, and it was from this that the speed of the Allied ships exceeded the rate of loss for the first time. If this were not the case, no matter how strong the shipbuilding capacity of the United States and Britain was, and how thick the tonnage of merchant ships was, they would inevitably be dragged down by the unrestricted submarine warfare of the Axis powers within a few years under the desperate exchange ratio of the previous one.

But this did not reassure Roosevelt, because Germany's new submarines only began to become the main force in this year, that is, the speed of German production of new submarines was far from the limit, and their production will continue to increase in the future. After basically abandoning radio contact at sea, the concealment of the new German submarines is simply incredibly strong, unless they accidentally fly into the passive sonar of Allied anti-submarine ships (because the United States and Britain anti-submarine Jishu are more advanced, and the size of surface ships is larger, so although German submarines are also equipped with passive sonar, the detection distance is relatively closer). ), otherwise it would not have been detected by the Allies at all.

In the following two months, the Allies only "suspectedly" sank a total of 2 new German submarines, which is undoubtedly the most proven. The rapid increase in production and the fact that the losses were almost negligible, that is to say, the number of German submarines in the future would continue to increase at an alarming rate, even if the efficiency of single-boat combat would drop significantly, as long as the number increased, it could be compensated

In particular, Argentina, the second largest country in South America, which has always been pro-German, has secretly supplied German submarines, making the German submarine force rely on Casablanca (Arab Federation) and Dakar (Senegal [Note 1]), two important supply ports (Note 2). The traffic between the north and south of the Atlantic Ocean was almost completely cut off

Under the current situation that the Panama Canal has not been opened so far, this terrible large slash will definitely deal a fatal blow to the already bad logistics supply of Australia's six or seven hundred thousand Allied troops, but Argentina is a South American power after all, even if the United States cannot concentrate its full strength, it is difficult to crush it to death at once, and pressing too hard may make it determined to join the Axis powers, so Roosevelt decided to start with the other end of this big slash first, as long as the snake's head is cut off, this damn naval blockade line will not be maintained

Note 1: As mentioned earlier, the Islamic Republic of Senegal was one of the countries in Senegal that the Islamic Republic of Senegal was one of the countries that sent people south to liberate large swathes of Western colonies and helped the locals establish republican governments. After the Arab Confederation entered the axis, a settlement was reached with the Vichy French government under the mediation of the mustache, and Kerim recognized the special interests of Vichy France in the former French colonies of Africa except for the Arab Federation itself, so the Vichy French navy soon resumed its presence in Dakar, which was an important military port in the past

Note 2: Although the distance is a little farther, the teardrop-shaped submarine developed by Germany in history has a terrifying endurance of 15,500 nautical miles (that is, 29,000 kilometers), not to mention this time and space, so there is no difficulty in replenishment when the German snorkel drop-shaped submarine travels back and forth between the two sides of the Atlantic and completes combat missions. (To be continued......)