FlyingDutchman, you wrote,
Weren't there even torpedo-nets and the likes ? - Much like at Pearl Harbor, none that I have been able to find any proof of. AA guns with little ammo and fighters posted miles away etc., etc. A non-functional radar air warning system. Even though the British air strike on the Italian fleet at Taranto was known, it seems that the US felt that the Japanese didn't have the technology/training/aircraft needed to repeat it elsewhere. Plus, Panama is so far from Japan. Just like with 9/11 (using hijacked suicide airliners) our hindsight now is easy but in Dec.'41, before the Japanese had hit Pearl Harbor by air, any such air attack on Panama would have been an equally nasty and probably total, surprise. IMO.
So any Japanese attempts at a portvisit will only raise American suspicion, instead of lowering it. Yet historicay such happened. When the embargo was slapped on the Japanese tried to source raw materials elsewhere, notably from South America. The US itself allowed several repatriation liners to vist the US West Coast via Honolulu. IJN training flotillas had been going on round-the-world cruises for years to give each year's class of new navy recruits their first taste of life at sea.
I don't forsee any greast amount of "butterfly" type effects since I'm not talking about that great an increase in Japanese efforts over and above the OTL. So an IJN carrier goes along on the trip instead of the OTL heavy cruiser ? News of this level of substitution would not start a war immediately. Considering the low number of warplanes carried by Hosho I'd expect the over-confident Americans to believe that their newly Panama based P-36s could handle any possible threat. Remember that the US armed forces didn't know much at all about the newish Zero's capabilities in Dec.'41.
FDR knew that America wasn't yet ready for war and didn't want to antagonize the Japanese too too much. He had to do something to signal US displeasure but even his oil embargo was "accidental" in that he only intended to ban high octane avgas from sale to Japan. His bureaucrats though, led by one Dean Acheson (sp ?), made it a total ban on all oil products and forced a war before the US was anywhere near ready to fight.
Who knows how the US would have responded to such a Japanese drive ? - Historically we know that the US was largely asleep at the wheel and did not much of anything militarily in response to the OTL Japanese efforts. Diplomatic discussions with several Central and South American governments were more than enough to ensure that the Japanese didn't get the oil and minerals that they searched for but in my scenario the Japanese effort is just a cover for the presence of a small carrier in the Eastern Pacific, anyway. Neither the Japanese nor I expected any real successes in buying South American oil but they had to try, even if just as a cover for their preparations to seize the NEI oil production areas.
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CanadianGoose, you wrote,
It would take chemical testing (or human tasting, RDX tastes like bitter sh...t) of every sack to get the difference. - More likely, one 5 minute pass thru the ship's cargo hold by a trained "sniffer" dog.
RDX posing like sugar? Yep, no problemo. No matter who did it (I'm very skeptical of "Putin's minions" version, pushed by very aggressive group of conspiracy theorist editors), they packed RDX in sacks marked "sugar" and nobody saw the difference. In fact, I got my idea from those events. - Sorry, my fault for not specifying a 1941 source that details Japanese use/production of RDX in large tonnage quantities back then. The record of a 1999 attack in Russia, some 58 years later, hardly proves the possibility of a 1941 Japanese sabotage attack with RDX in Panama.
By your logic the Panama Canal could have been blown up in Dec.'41 by a Russian atom bomb, based on 1947 Russian a-bomb test reports. Try again.
Japanese shipping was banned from the Panama Canal long before Dec.'41 so you'll have to use a neutral ship to carry your "surprise package" thru Panama. What happens if one of those civilian crewmen/officers notices some unusual wiring coming out of the piles of "sugar" sacks in the hold ? What happens should a rat chew through one of those fuse wires during the long voyage ? What if one of your detonator batteries goes "flat" ? Could a lightning strike on the freighter set off the RDX ? Perhaps a shift in the cargo pulls on the detonator wires and breaks the firing circuit ? What if one of the armed US Marine guards put on board every ship transitting the Canal should notice an odd wire or two or even object to a crewman entering a cargo hold during the transit ? There is no good reason for any crewman to so enter and a loaded rifle adds authority to any "stop where you are" demand.
The US Marines were authorized (and in the OTL known to) lock unco-operative captains and their crews in their cabins for the transit, should such seem advisable to the US Lt. in charge of the secruity team on board.
You have yet to prove that the Japanese had the quantites of RDX needed and IF they did, how would you convince the IJN battleship admirals to give up large tonnage quatities of their best explosive, just as a war for national survival is about to start ? When just a few conventional torpedoes (about 8, or 10 with spares included) can get the job done instead.
Too many failure possibilities, even without a sniffer dog or two, don't you think ?
