Perhaps the BEST B1G Forum anywhere, here at College Football Fan Site, CFB51!!!

Submarines struggle to operate in WW 2 where there were decent land airbases nearby, especially if planes had radar.  I imagine we pretty well saturated the exits of the Canal with air cover early in the war.  And I don't know how long a Japanese sub could "linger" due to fuel and supply issues.

One probable mistake Yamamoto made after Pearl Harbor was the attack in the Indian Ocean, those weren't very strategic I think.

Jeebis one would think Yamamoto would have his subs there licking their chops - if it wasn't twice as far from Japan as Hawaii. That plan would have made sense logistically during the early stages of the Pacific war, when the US Navy had half of its 6 carriers on the opposite oceans . There were air bases and coastal guns at both ends of the canal. Still it would have been a great choke point for ambush. The IJN had quite advanced machines and "long lance" torpedoes at the time but didn't coordinate their deployments effectively from what I've read. In hindsight strategically perhaps they should have skipped speading themselves to thin around the vastness of the Pacific. But prolly didn't think the USA could reload at break neck speed. Logistics,planning and industry probably caught up to Hirohito's over confidence. But what if......

They actually built a submarine that could carry a plane and launch it. The intention was to use the submarine to get within range of the Panama Canal then launch the plane with munitions to destroy some critical part of the canal.

If that had existed and been functional in time to use it simultaneously with Pearl Harbor and all the rest of their attacks on December 7/8, 1941 it might have actually worked.

At the end of the day, even if it had worked I don't think it would have been more than a relatively minor annoyance for the United States. The US built the canal so I consider it axiomatic that the US could repair any damage done to the canal and realistically one plane couldn't do all that much damage even with a direct hit. It might, however, have put the canal out of action for a few months which would have drastically slowed the US response because Hornet and other ships then in the Atlantic would either have had to stay in the Atlantic until the canal was repaired, go around Africa, or go around South America.

for Badge, when he buys a bigger yacht 

The whole attempt just illustrates how utterly hopeless the Japanese were. They dropped two bombs in the hope that those would start forest fires. 

I had to Google it but 76 kg is ~167#. So the total bomb load was a hair over 300# and this was supposed to work?

The pictured B29 carried 5,000 to 20,000 pounds of bombs depending upon range and the United States built almost 4,000 of them and sent them over Japan in waves of hundreds of planes. 

THIS DAY IN HISTORY: 
Hymen Lipman Patents Pencil with Attached Eraser (1858)
In prehistoric times, lumps of colored earth or chalk were used as markers. The so-called lead pencil—a rod of graphite encased in wood—first came into use in the 16th century. However, it was not until the 19th century that the eraser was added—an innovation that earned Hymen Lipman a patent in 1858. In 1862, he sold his patent to Joseph Reckendorfer for $100,000.

ARTICLE OF THE DAY: 

The Plague Riot
In the spring of 1771, an outbreak of bubonic plague swept through Moscow. Authorities instituted a number of policies in an attempt to contain the epidemic, but the severe measures were unpopular with the general public. Factories and stores were shut down, and the economy was essentially at a standstill. Fearful, and faced with acute food shortages, the people took to the streets in an uprising that would later be known as the Plague Riot.