alternatehistory.com

http://en.wikipedia.org/wiki/Merchant_submarine
The submarines were built in 1916 by a private shipping company created for the enterprise, the Deutsche Ozean-Reederei, a subsidiary company of the North German Lloyd shipping company (now Hapag-Lloyd) and the Deutsche Bank.[1] They were intended to travel the route from Germany to the neutral U.S., bringing back the required raw materials. As the U.S. would not profit enough from receiving German currency, the ships were to carry trade goods both ways.[2]
Britain soon protested with the U.S. against the use of submarines as merchant ships, arguing that they could not be stopped and inspected for munitions in the same manner as other vessels. The U.S., under diplomatic pressure for supposedly showing favoritism while having declared itself neutral, rejected the argument. Even submarines, as long as they were unarmed, were to be regarded as merchant vessels and accordingly would be permitted to trade.[1]
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Deutschland was one of seven submarines designed to carry cargo between the United States and Germany in 1916, through the naval blockade of the Entente Powers.

She carried 750 tons of cargo in total

http://en.wikipedia.org/wiki/German_submarine_Deutschland
American submarine pioneer Simon Lake visited the Deutschland while she was in Baltimore, and made an agreement with representatives of the North German Lloyd line to build cargo submarines in the US, a project which never came to fruition.[7
http://en.wikipedia.org/wiki/Simon_Lake

http://en.wikipedia.org/wiki/German_submarine_Bremen
The Bremen departed Bremerhaven in September 1916 for Norfolk, Virginia, commanded by Kapitaenleutnant Karl Schwartzkopf, and reportedly carrying financial credits for Simon Lake to begin building cargo submarines for Germany.

What if the Bremen arrives in Norfolk and delivers the necessary money to Simon Lake to start building merchant submarines for Germany? There was another thread about this that I cannot find on search.

Let's say that Germany continues to build and maintain the merchant subs so that 7 are operating at one time, plus a private US company builds merchant subs that are staffed by either American volunteers (pro-CP US citizens I'd think) or German merchant sailors trapped in the US by the British blockade. So by early 1917 there are more than a dozen merchant subs plying the Atlantic, each carrying between 700-1,000 tons of goods. Each trip takes roughly 1 month and ensures critical industrial chemicals, rubber, and certain rare earth metals are available, which otherwise would be denied Germany.

What does this mean for international relations? Does the US challenge the British blockade sooner, so as to open up the lucrative Central European markets? Do the Austro-Hungarians get involved? Do the Germans still launch their unrestricted submarine war if they had some access to US markets and increasing good will in the US over these missions? Do the 750 ton missions by the subs help ease critical shortages in German industry to make them a vital and viable strategy, at least long enough for the US to stop loaning money to the Entente and challenge the blockade?
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