PS: Thank you for the book friend "Wangyun Mountain People" for your re-reward, and continue to ask for recommendation votes ^_^

Although the occupation of Iceland had greatly benefited the United States from a strategic point of view, Roosevelt had never felt the heavier pressure it had suffered since the attack on Pearl Harbor, and he was particularly disturbed by the fact that he found that the Axis powers were far more powerful than he had expected, and that even if the United States had a great business, if it showed its flaws, it would have suffered heavy losses, and with the American system, it was impossible not to make mistakes in the early stages of the war (Churchill once hurt the Americans, saying" They always have to try all the wrong ways before they can find the right one. Roosevelt could only pin his hopes on America's unrivaled industrial capacity and the powerful mobilization system he created at the risk of being ousted from power, emulating the Soviet economic system

By the beginning of 1942, the United States was building more than 400 combat ships at the same time, more than 30 percent more than the total number of all its current ships, and light ships such as destroyers were built at an astonishing speed with the help of the assembly line shipbuilding method, and it often only took a few months from the beginning of construction to the completion of service, so although the US Navy suffered heavy losses in this month, the losses of non-combat ships such as light ships and transport ships could be completely made up in only two or three months. And it's stronger than the ones that were lost

Due to the long construction time of the capital ships, it is difficult to quickly make up for the huge losses in the Pearl Harbor incident, but in this regard, the United States' powerful shipbuilding capabilities are still jaw-dropping, and the United States lost three aircraft carriers in the Pearl Harbor incident. And before that, the United States had a full 11 new Essex-class aircraft carriers under construction (this is the case in history, as are the battleships mentioned below, which alone shows that the United States has long been interested in hegemony, otherwise would it be to build so many aircraft carriers and battleships for fishing?). More than half of them will be completed in 1942, and after the outbreak of the Pearl Harbor incident, the U.S. government decided to convert six (Note 1) Cleveland-class light cruisers that had already entered service or had completed their hulls into light aircraft carriers (the aircraft carriers converted from warships were not necessarily worse than the newly-built ones, and the Independence class was said to be light aircraft carriers, and its comprehensive performance was actually stronger than that of Japan's Wyvern-class medium-sized aircraft carriers). ), all are expected to be completed and commissioned within a year

And on the part of battleships. The United States lost only 4 old battleships at Pearl Harbor. However, before that, the United States had 13 battleships under construction at the same time, of which 9 were Iowa-class battleships that were more advanced than any of the current battleships in service, and due to the news of the launch of two German Hindenburg-class battleships in Qingdao, China, the construction of the American Montana-class battleships that died in the middle of history was later carried out. This brought the total number of battleships under construction in the United States at the same time in 1942 to a terrifying 18. Of course, that's all for later

It's worth mentioning though. Another important reason why the U.S. government did not terminate the construction of the Montana-class super battleships was that the audacity of Yamaguchi did not return to participate in the Nanyang War after capturing Oahu and receiving a large number of supplies. Instead of immediately attacking the nearby islands under the control of the American army, they immediately concentrated most of the ships and thousands of marines on an expedition to Panama, which again surprised the Americans.

As a result, in the face of the overwhelming naval and air superiority of the Japanese army, although the few US troops in Panama resisted stubbornly, this small Central American country was still occupied by the Japanese army without any suspense, and although the United States itself had formed a large number of land forces, it was too late to rescue in a day or two, and this did not consider the problem of having to borrow from Mexico and other countries, and even if the United States could send reinforcements as quickly as possible, marching on the narrow terrain in Central America that lacked depth would be difficult because of the attack of Japanese carrier-based aircraft, as for the sea route, the main force of the Atlantic Fleet is still fighting in Iceland and has not returned, what will the United States use to protect the ground forces from being killed by the huge Japanese fleet?

However, even if the American reinforcements did not arrive in time to help, the Japanese army could not stay in Panama for a long time, because the Japanese navy was unable to protect such a long supply line, so the Grand Fleet could not stay here for a long time, and as soon as the fleet left, with the strength of the Japanese ground forces, it would definitely not be able to resist the all-out attack of the US Navy and Army. Therefore, the Japanese army withdrew all of them within a few days after occupying Panama, but they still achieved their goal, and before leaving, the Japanese army blew up by engineering blasting (the locks are much more fragile than the reservoir dams, the latter can be blown up, and the locks are naturally even more problematic). At the beginning, the United States spent a lot of effort to repair the six Panamanian locks. This not only directly cut off the Panama Canal, an extremely important communication route, but also created a big problem for the United States to repair in the future

During the construction of the Panama Canal, the Americans built three locks on each of the two sections of the canal in order to take advantage of Lake Gatun in the Isthmus of Panama to prevent the lake from leaking 26 meters above sea level on both sides of the isthmus. However, this design also made it very convenient for the Japanese to destroy the canal, and the locks were completely destroyed after the explosion, and even with the strong strength of the United States, they could not repair them, and they had to build new locks to replace them, and before the Americans had to clean up the ruins of the destroyed locks and the mud and rocks caused by the discharge of the lake

Because of this, the U.S. government would need to invest more in the Panama Canal than it would have to build a new Panama Canal from scratch, especially since it was still during the Great War of Shijie. Obviously, at least until the end of World War II, the Panama Canal is no longer a line of communication, and this is the purpose of Yamaguchi Tawen's fleet to attack Panama.

After the Panama Canal was cut off, if the United States wanted to transfer its fleet from the Atlantic Ocean to the Pacific Ocean to participate in the war, it could only make a detour through Cape Horn, the southernmost point of South America, which was more than 10,000 kilometers longer than the previous shortcut through the Panama Canal, which not only meant a large increase in fuel consumption, but also made it very troublesome for the US Government to mobilize the two-ocean fleet, and if it was not done well, it would also give the enemy various opportunities to break through, just like the Tsarist fleet in the Russo-Japanese War.

In addition, the extra range of more than 10,000 kilometers will also put American warships and merchant ships in greater danger, and now that German submarines are raging and difficult to control, the longer the voyage means the greater the possibility of being attacked; And the longer the route, the more escort ships are needed, which is also a huge additional expense, although the United States can afford it completely, but it is not a good thing to spend a lot of money and occupy a large number of ships

Note 1: Due to the loss of the Battle of Iceland, the United States has three fewer Cleveland-class light cruisers available for modification than in history, but because the construction of the Essex-class aircraft carrier was not partially cancelled as in history, the number of ships built by the United States in this time and space is only a lot more than in history. (To be continued......)